Lincoln Corsair: Anti-Lock Brake System (ABS) and Stability Control / Diagnosis and Testing - Anti-Lock Brake System (ABS) and Stability Control

Normal Operation and Fault Conditions

If DTC U0140:00 or U0422:00 is present with U300A:29, diagnose the lost communication DTC first.

The ABS module, hydraulic pump and solenoid valves require an operating voltage between 10 and 17 volts. The parking brake system requires an operating voltage of 9 volts or higher. The ABS module receives this voltage from the BJB . The ABS module has 2 ground circuits. Excessive resistance or an open in one or more of these circuits, a discharged battery or a inoperative charging system results in the ABS module setting a DTC .

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Fuse(s)
• Wiring, terminals or connectors
• Charging system concern
• 12-volt Battery
• EBB unit ( HCU and ABS module assembly)

Visual Inspection and Pre-checks

• Make sure the vehicle battery terminals and cables are free of any corrosion and other contaminants.
• Make sure the vehicle battery terminals are tightened to their correct torque specifications.
• Make sure all EBB and ABS module fuses in the BJB are OK.

Normal Operation and Fault Conditions

This DTC is pre-set in a new ABS module and can only be cleared when the Brake System Service Bleed is successfully carried out. REFER to: Brake System Pressure Bleeding (206-00 Brake System - General Information, General Procedures).

DTC Fault Trigger Conditions

Possible Sources

• Brake System Service Bleed not complete

Normal Operation and Fault Conditions

The ABS module incorporates a function for testing the vehicle on a dynamometer to prevent wheel speed sensor Diagnostic Trouble Codes (DTCs) from setting during testing. The PCM sends a message to the ABS module when the vehicle is setup for testing. When the ABS module receives this message it knows to ignore discrepancies between the front and rear wheel speed sensors.

The ABS module exits the test mode automatically when the PCM sends the exit message, the ignition is set to OFF, either of the non-driven wheels exceeds 20 km/h (12 mph) or a wheel speed sensor DTC is detected on any wheel speed sensor.

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• ABS module in test mode

Visual Inspection and Pre-checks

• Drive the vehicle above 20 km/h (12 mph). Stop and cycle the ignition from ON to OFF and back to ON. Carry out the ABS module self-test. If the DTC returns, retrieve and diagnose all PCM Diagnostic Trouble Codes (DTCs).

Normal Operation and Fault Conditions

With the ignition ON, the sends messages to the BCM ABS module over the HS-CAN1 through the GWM . If the ABS module does not receive these messages within the allotted time frame or if the messages contain invalid data, the module sets a DTC . This can be due to a BCM failure, a circuit failure on the network or an excessive load on the network. For information on the messages sent to the ABS module by the BCM , REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Network communication concern
• GWM
• BCM

NOTE: This test requires the use of at least 2 ignition keys (passive or IKT ) programmed to the vehicle; one admin ignition key and one restricted ignition key.

Normal Operation and Fault Conditions

The stability-traction control disabled indicator (sliding car OFF icon) in the IPC provides traction control system status to the driver.

When the driver deactivates the traction control, the APIM sends a message to the GWM over the HS-CAN3 indicating the driver has requested the traction control to be disabled. The GWM relays this message to the ABS module over the FD-CAN . The ABS module continues to monitor for excessive wheel spin, but no longer takes any action when a traction event is detected.

After receiving the traction control status message from the APIM , the ABS module then sends a message to the GWM over the FD-CAN to illuminate the stability-traction control disabled indicator (sliding car OFF icon). The GWM relays this message to the IPC over the HS-CAN3 . The IPC responds by illuminating the stability-traction control disabled indicator (sliding car OFF icon). The traction control system remains deactivated until the driver changes the traction control state in the message center or until the ignition is cycled.

If equipped, MyKey allows users to configure traction control to be either always on or selectable. If a MyKey restricted key is in use with the MyKey traction control feature configured to always on, traction control cannot be disabled. An admin key must be used to enable and disable traction control.

Possible Sources

• A MyKey restricted key is in use
• Network communication concern
• APIM concern

Normal Operation and Fault Conditions

The ABS module may set an over-voltage DTC if the vehicle has been recently jump started, the battery has been recently charged or the battery has been discharged. The battery may become discharged due to excessive load(s) on the charging system from aftermarket accessories or if the battery has been left unattended with the accessories on.

The ABS module, hydraulic pump and solenoid valves require an operating voltage between 10 and 17 volts. The parking brake system requires an operating voltage of 9 volts or higher. The ABS module receives this voltage from the BJB . The ABS module has 2 ground circuits.

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Charging system concern
• EBB unit ( HCU and ABS module assembly)

Normal Operation and Fault Conditions

The ABS module monitors all base brake, anti-lock brake, traction control and stability control functions and features. If a system error occurs which could cause irreparable damage to the system, the ABS module disables the EBB unit. The base brake system still functions, but there is no brake boost assist. This can also occur if the EBB unit loses power or ground.

System over-voltage combined with other specific circumstances may cause the EBB unit to provide excessive brake assist or a "touchy" pedal, where the brakes apply heavily with a light application of the brake pedal.

In either of these cases, no brake assist or too much brake assist, the ABS module sets Diagnostic Trouble Codes (DTCs) indicating possible concerns.

Possible Sources

• Diagnostic Trouble Codes (DTCs) preset in the ABS module

Visual Inspection and Pre-checks

• Retrieve and diagnose all ABS module Diagnostic Trouble Codes (DTCs)

Normal Operation and Fault Conditions

The ABS module uses an internal solid state switch to operate the hydraulic pump motor. The ABS module tests the hydraulic pump motor by activating it for 30 milliseconds. The ABS module monitors the voltage drop across the hydraulic pump motor while the pump motor is being activated. After 30 milliseconds have passed, the ABS module stops applying voltage to the pump motor and monitors the voltage the spinning hydraulic pump motor is generating and the voltage drop across the hydraulic pump motor solid state switch. If the monitored voltages are not within the specifications, the ABS module sets one or more Diagnostic Trouble Codes (DTCs).

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Fuses
• Wiring, terminals or connectors
• EBB unit ( HCU and ABS module assembly)

Visual Inspection and Pre-checks

• Make sure the vehicle battery terminals and cables are free of any corrosion and other contaminants.
• Make sure the vehicle battery terminals are tightened to their correct torque specifications.
• Make sure all EBB and ABS module fuses in the BJB are OK.

Normal Operation and Fault Conditions

The brake fluid level switch is hardwired to the ABS module, the module monitors the switch and brake fluid level. If a circuit fault or fluid loss is detected, a DTC is set.

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Wiring, terminals or connectors
• Leak in the hydraulic system
• Brake fluid level switch
• EBB unit

• Ignition ON.

• Using a diagnostic scan tool, retrieve all ABS module Diagnostic Trouble Codes (DTCs).

• Note all ABS module Diagnostic Trouble Codes (DTCs).

• Thoroughly inspect the brake system hoses, tubes, joint connections, brake caliper and EBB unit for any signs of an obvious leak.

Normal Operation and Fault Conditions

This DTC is pre-set in a new ABS module and can only be cleared when the brake system has been successfully bled.

The brake system requires a certain amount of hydraulic fluid for correct operation. When the brake system is filled, the ABS module sets a PID . If the vehicle is operated and the ABS module detects this PID has not been set, a DTC is set.

CARRY OUT the Brake System Service Bleed. REFER to: Brake System Pressure Bleeding (206-00 Brake System - General Information, General Procedures).

DTC Fault Trigger Conditions

Possible Sources

• Brake hydraulic system has not been filled to specified level and successfully bled

Normal Operation and Fault Conditions

With the ignition in RUN, the ABS module continuously monitors the base brake system, the ABS , and the stability control system. If there is a concern present in one of the systems, the ABS module sets a DTC and sends a message to the GWM over the FD-CAN , the GWM relays this message to the IPC . Once the message is received, the IPC illuminates the appropriate warning indicator.

The IPC also illuminates the warning indicators as part of a self test when the ignition is set to RUN or ACC. REFER to: Instrument Panel Cluster (IPC) - System Operation and Component Description (413-01 Instrumentation, Message Center and Warning Chimes, Description and Operation).

Possible Sources

• Diagnostic Trouble Codes (DTCs) present in the ABS module
• Low brake fluid
• Brake fluid level sensor
• ABS or stability control concern
• IPC concern

Visual Inspection and Pre-checks

• Check for ABS module Diagnostic Trouble Codes (DTCs), if there are no Diagnostic Trouble Codes (DTCs) present, refer to Section 413-01 to diagnose the IPC warning indicators.

Normal Operation and Fault Conditions

The hill start assist feature automatically engages when the conditions for engagement have been met. The ABS module receives messages from the RCM indicating vehicle incline and the PCM indicating the vehicle is not parked. The wheel speed sensors and EBB internal brake pedal switch indicate the vehicle has fully stopped. Once these conditions are met, the ABS module closes the isolation valves in the EBB which temporarily holds the vehicle in place.

In the case of a system error, messages are displayed in the message center and Diagnostic Trouble Codes (DTCs) may be set in one or more modules.

Possible Sources

• Network concern
• RCM concern
• PCM concern
• FCIM concern
• ABS module (part of the EBB unit)

Visual Inspection and Pre-checks

• Retrieve and diagnose all Diagnostic Trouble Codes (DTCs) from the modules listed in the Possible Causes.

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may cause damage to the connector.

Normal Operation and Fault Conditions

Active wheel speed sensors generate a voltage signal proportional to wheel speed which is sent to the ABS module. Each wheel speed sensor is connected to the ABS module through 2 wires and a connector at each wheel speed sensor. The 2 circuits provide both sensor power and sensor signal return. When the ignition mode is set to ON, the ABS module carries out a self-test by sending a reference voltage through the wheel speed sensors and their circuitry.

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Wiring, terminals or connectors
• Wheel speed sensor
• ABS module (part of the EBB unit)

Visual Inspection and Pre-checks

• Make sure the wheel speed sensor harness is routed correctly and is undamaged.
• Make sure the wheel speed sensor electrical connector is free from any corrosion or other contaminants.

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may cause damage to the connector.

Normal Operation and Fault Conditions

Active wheel speed sensors generate a voltage signal proportional to wheel speed which is sent to the ABS module. Each wheel speed sensor is connected to the ABS module through 2 wires and a connector at each wheel speed sensor. The 2 circuits provide both sensor power and sensor signal return. When the ignition mode is set to ON, the ABS module carries out a self-test by sending a reference voltage through the wheel speed sensors and their circuitry.

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Wiring, terminals or connectors
• Wheel speed sensor
• ABS module (part of the EBB unit)

Visual Inspection and Pre-checks

• Make sure the wheel speed sensor harness is routed correctly and is undamaged.
• Make sure the wheel speed sensor electrical connector is free from any corrosion or other contaminants.

Normal Operation and Fault Conditions

The traction control switch is used to switch the traction control system on or off. When the traction control switch is pressed, the FCIM receives a ground signal from the switch and sends a message over the HS-CAN3 to the GWM . The GWM sends the message out to the IPC and the ABS module. When the IPC receives the message, the module illuminates the stability-traction control OFF indicator. When the ABS module receives the message, the module takes the necessary action depending on the switch inputs and traction control message.

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• A MyKey restricted key is in use
• Wiring, terminals or connectors
• Insturment panel console switch assembly
• FCIM

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may cause damage to the connector.

NOTE: Diagnostics in Workshop Manual Section 206-05 must be carried out before proceeding with this test.

Normal Operation and Fault Conditions

The EBB unit ( HCU and ABS module assembly) controls the EPB system.

REFER to: Parking Brake - System Operation and Component Description (206-05 Parking Brake and Actuation, Description and Operation).

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

Possible Sources

• EPB system concern

• Verify all applicable diagnostics in Workshop Manual section 206-05 for the EPB concern have been carried out.

Normal Operation and Fault Conditions

The EBB unit ( HCU and ABS module assembly) provides power assist to the hydraulic brake system. REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

To diagnose power brake assist concerns, retrieve and repair all Diagnostic Trouble Codes (DTCs) from the ABS module.

Possible Sources

• EBB unit ( HCU and ABS module assembly) concern

Normal Operation and Fault Conditions

The ABS module carries out self tests during operation, the module also monitors various inputs and compares the values to what is expected. If the values received are out of range, are not what is expected, or if any of the self tests fail, the ABS module sets a DTC .

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• HS-CAN concern
• Incorrect sensor input
• Stuck valve
• EBB unit ( HCU and ABS module assembly)

Normal Operation and Fault Conditions

During new module installation, configuration files are loaded into the new module being replaced. If a discrepancy is detected between the modules or an incomplete programming procedure is carried out, a DTC is set.

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Incomplete programming procedure
• Improper programming procedure
• EBB unit ( HCU and ABS module assembly)

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may cause damage to the connector.

Normal Operation and Fault Conditions

The wheel speed sensor uses the tone ring to generate a square wave signal proportional to wheel speed which is sent to the ABS module. The front wheel bearing, rear axle shafts, tone rings and wheel speed sensors must be undamaged and free from any contamination to produce a clean signal for use by the ABS module. Also, all 4 tires and wheels must be of the same manufacturer recommended size for the wheel speed sensor to generate an accurate wheel speed signal.

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Tire Pressure
• Incorrect or mismatched tire
• Wiring, terminals or connectors
• Wheel bearing
• Wheel speed sensor encoder ring
• Wheel speed sensor
• ABS module (part of the EBB unit)

Normal Operation and Fault Conditions

The ABS module uses information from the wheel speed sensors, RCM and PSCM to determine when stability control intervention is necessary to help stabilize the vehicle. The ABS module uses the EBB unit to modulate the brake fluid pressure to the brake calipers and continues to monitor the sensor and module input until the instability event has been corrected. Once the sensors and modules indicate the instability event has been corrected, the ABS module deactivates the EBB unit. Under inflated tires, wheels and tires that do not match VC label specifications, suspension and steering damage, and one or more sensor failures contribute to the ABS module setting this DTC .

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Tire pressure
• Wiring, terminals or connectors
• Chassis damage
• Steering damage or alignment
• Wheel speed sensor
• RCM
• PSCM

Normal Operation and Fault Conditions

With the ignition ON, the PSCM sends messages to the ABS module over the HS-CAN2 through the GWM . If the ABS module does not receive these messages within the allotted time frame or if the messages contain invalid data, the module sets a DTC . This can be due to a PSCM failure, a circuit failure on the network or an excessive load on the network. For information on the messages sent to the ABS module by the PSCM , REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Network communication concern
• PSCM

Normal Operation and Fault Conditions

When the ignition is set to ON, the ABS module and the BCM share VIN information through the GWM over the CAN .

When a new EBB unit is installed, the ABS module must be programmed with the vehicle information. REFER to: Module Configuration - System Operation and Component Description (418-01 Module Configuration, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• BCM configuration
• ABS module configuration

Normal Operation and Fault Conditions

The ABS module receives vehicle yaw rate, lateral acceleration, longitudinal acceleration and roll rate from RCM over the HS-CAN2 , through the GWM . The yaw rate sensor, lateral accelerometer, longitudinal accelerometer and roll rate sensor are all contained in the RCM . A failure of the HS-CAN2 , an internal failure of the RCM or the internal sensors causes the ABS module to set one or more Diagnostic Trouble Codes (DTCs).

DTC Fault Trigger Conditions

Possible Sources

• Network communication concern
• Incorrectly installed RCM
• RCM

Normal Operation and Fault Conditions

With the ignition ON, the PCM sends messages to the ABS module through the GWM over the HS-CAN . The TCM is an internal component of the PCM . If the ABS module does not receive these messages within a certain time frame (usually less than 1 second), the ABS module sets a DTC . For information on the messages sent to the ABS module by the PCM , REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Network communication concern
• PCM

Normal Operation and Fault Conditions

The ABS module carries out a self-check each time the ignition mode is changed to RUN. If the ABS module detects a fault, one or more Diagnostic Trouble Codes (DTCs) is set.

DTC Fault Trigger Conditions

Possible Sources

• Wheel speed sensor input concern
• Wheel speed sensor

Normal Operation and Fault Conditions

The ABS module monitors various inputs and compares the values to what should be expected. If the values received are out of range or not what should be expected, the ABS module sets a DTC .

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Incorrect sensor input
• Air trapped in the hydraulic system
• EBB unit (electric boosted vehicles)
• ABS module and HCU assembly (vacuum boosted vehicles)

Normal Operation and Fault Conditions

The ABS module monitors various inputs and compares the values to what should be expected. If the values received are out of range or not what is expected, the ABS module sets a DTC . When a new ABS module or RCM is installed, the stability control sensors in the RCM must be initialized. This is accomplished using a diagnostic scan tool to run the ABS Calibration routine.

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• ABS Calibration routine not carried out
• RCM concern
• EBB unit ( HCU and ABS module assembly)

Normal Operation and Fault Conditions

The CCM is an internal component of the Advanced Driver Assistance Systems (ADAS) module.

The Advanced Driver Assistance Systems (ADAS) module receives information from the forward looking radar module along a private CAN . The Advanced Driver Assistance Systems (ADAS) module sends messages to the ABS module over the FD-CAN . If the ABS module does not receive these messages within the allotted time frame or if the messages contain invalid data, the module sets a DTC . This can be due to a Advanced Driver Assistance Systems (ADAS) module failure, a circuit failure on the network or an excessive load on the network. For information on the messages sent to the ABS module by the CCM and Advanced Driver Assistance Systems (ADAS) module, refer to the Network Message Chart in Section 206-09, Description and Operation in the Workshop Manual.

DTC Fault Trigger Conditions

Possible Sources

• Network communication concern
• CCM - part of the Advanced Driver Assistance Systems (ADAS) module

Normal Operation and Fault Conditions

With the ignition ON, the IPC sends messages to the ABS module through the GWM over the HS-CAN3 . If the ABS module does not receive these messages within a certain time frame, the module sets a DTC . For information on the messages sent to the ABS module by the IPC , REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Network communication concern
• GWM
• IPC

Normal Operation and Fault Conditions

With the ignition ON, the FCIM sends messages to the ABS module through the GWM over the MS-CAN . If the ABS module does not receive these messages within a certain time frame (usually less than 1 second), the module sets a DTC . For information on the messages sent to the ABS module by the FCIM , REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Network communication concern
• FCIM
• GWM

Normal Operation and Fault Conditions

With the ignition ON, the GSM sends messages to the ABS module over the HS-CAN2 through the GWM . If the ABS module does not receive these messages within the allotted time frame or if the messages contain invalid data, the module sets a DTC . This can be due to a GSM failure, a circuit failure on the network or an excessive load on the network. For information on the messages sent to the ABS module by the GSM , REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Network communication concern
• GWM
• GSM

Normal Operation and Fault Conditions

The ABS module uses several sensors (wheel speed, steering wheel rotation, stability control) to determine if ABS or stability control intervention is required. Accurate sensor readings rely on the vehicle being in good operational condition with as few mechanical and electrical concerns as possible. In addition, the wheels and tires must be within vehicle manufacturer's specifications as described on the VC label and the base brake system and parking brake system must be in good operational condition. If one or more of these items or systems are in need or repair or are not working at full capacity, the ABS or stability control system may activate when the driving condition does not warrant activation.

Possible Sources

• Wheels
• Tires
• Suspension components
• Parking brake dragging
• PSCM
• RCM

Normal Operation and Fault Conditions

With the ignition ON, the RCM sends messages to the ABS module over the HS-CAN2 . If the ABS module does not receive these messages within a certain time frame, the ABS module sets a DTC . For information on the messages sent to the ABS module by the RCM , REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).
.

DTC Fault Trigger Conditions

Possible Sources

• Network communication concern
• RCM

NOTE: The ATCM may also be called the traction control switch in other publications

Normal Operation and Fault Conditions

With the ignition ON, the ATCM sends messages to the ABS module over the HS-CAN 2. If the ABS module does not receive these messages within a certain time frame (usually less than 1 second), the ABS module sets a DTC . For information on the messages sent to the ABS module by the ATCM , refer to the Description and Operation in Section 206-09 of the Workshop Manual.

DTC Fault Trigger Conditions

Possible Sources

• Network communication concern
• ATCM

Normal Operation and Fault Conditions

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

With the ignition ON, the GWM sends messages to the ABS module over the HS-CAN2 . If the ABS module does not receive these messages within a certain time frame (usually less than 1 second), the ABS module sets Diagnostic Trouble Codes (DTCs). This can be due to a GWM failure, a circuit failure on the CAN or an excessive load on the network.

DTC Fault Trigger Conditions

Possible Sources

• Network communication concern
• GWM

Normal Operation and Fault Conditions

With the ignition ON, the VDM sends messages to the ABS module over the HS-CAN2 through the GWM . If the ABS module does not receive these messages within a certain time frame or if the messages contain invalid data, the ABS module sets Diagnostic Trouble Codes (DTCs). For information on the messages sent to the ABS module by the VDM , REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Fuses
• Network communication concern
• VDM

Normal Operation and Fault Conditions

The IPMA is an internal component of the Advanced Driver Assistance Systems (ADAS) module.

With the ignition ON, the IPMA sends messages to the ABS module the over the HS-CAN2 . If the ABS module does not receive these messages within a certain time frame, the module sets Diagnostic Trouble Codes (DTCs). This can be due to an IPMA failure, a circuit failure on the network or an excessive load on the network.

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Network communication concern
• IPMA - part of the Advanced Driver Assistance Systems (ADAS) module

Normal Operation and Fault Conditions

With the ignition ON, the AWD module sends messages to the ABS module through the GWM over the HS-CAN 2. If the ABS module does not receive these messages within the specified time frame, the ABS module sets a DTC . This can be due to a AWD module failure, a circuit failure on the network or an excessive load on the network. For information on the messages sent to the ABS module by the AWD module, REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Network communication concern
• GWM
• AWD module

Normal Operation and Fault Conditions

With the ignition ON, the PAM sends messages to the ABS module through the GWM over the CAN . If the ABS module does not receive these messages within a certain time frame, the module sets one or more Diagnostic Trouble Codes (DTCs). This can be due to an PAM failure, a circuit failure on the network or an excessive load on the network. For information on the messages sent to the ABS module by the PAM , REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Network communication concern
• PAM
• GWM

Normal Operation and Fault Conditions

With the ignition ON, the SODL and SODR send messages to the ABS module through the GWM over the CAN . If the ABS module does not receive these messages within a certain time frame, the ABS module sets one or more Diagnostic Trouble Codes (DTCs). This can be due to a SODL or SODR failure, a circuit failure on the CAN or an excessive load on the network. For information on the messages sent to the ABS module by the SODL and SODR , REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Network communication concern
• SODL
• SODR
• GWM

Normal Operation and Fault Conditions

Vehicles equipped with EPB are also equipped with an auto hold feature. This feature must be enabled by the driver by pressing the auto hold switch once the driver seatbelt is buckled and the driver door is closed.

Pressing the auto hold switch in the FCIM enables the auto hold feature, but does not activate auto hold. When the switch is pressed, the FCIM sends a message to the ABS module indicating the system has been enabled. The ABS module then waits for messages from the RCM and BCM as well as ABS sensor information to indicate the auto hold feature can be activated. Once all criteria has been met, the ABS module activates the auto hold feature.

In the case of a system error, the instrument cluster displays messages and icons.

Possible Sources

• Network communication concern
• FCIM concern
• ABS module

Normal Operation and Fault Conditions

With the ignition ON, the IPMB sends messages to the ABS module over the HS-CAN 2. If the ABS module does not receive these messages within the allotted time frame, the module sets a DTC . This can be due to an IPMB failure, a circuit failure on the network or an excessive load on the network. For information on the messages sent to the ABS module by the IPMB , REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Network communication concern
• IPMB - part of the Advanced Driver Assistance Systems (ADAS) module

Normal Operation and Fault Conditions

The HEV PCM may also be known as the SOBDM or the ICS module.

With the ignition ON, the SOBDM sends messages to the ABS module through the GWM over the HS-CAN . If the ABS module does not receive these messages within a certain time frame (usually less than 1 second), the ABS module sets a DTC . For information on the messages sent to the ABS module by the SOBDM , REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Network communication concern
• GWM
• SOBDM

Normal Operation and Fault Conditions

The EBB contains several hydraulic valves, hydraulic pressure sensors, a linear actuator and a pump motor. These components work in conjunction to provide the force necessary to bring the vehicle to a stop. The ABS module monitors these components for internal faults. If a fault occurs which impacts the base braking system, the ABS module sets one or more Diagnostic Trouble Codes (DTCs) and illuminates the red brake warning indicator.

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Air trapped in the hydraulic system
• External brake system leak
• Internal EBB unit leak
• EBB unit internal failure

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may cause damage to the connector.

Normal Operation and Fault Conditions

The EBB unit uses a motor to pressurize the brake system and to operate the ABS , ESC , RSC and other stability control features. The ABS module monitors the motor performance and sets a DTC when a motor fault is detected.

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Fuses
• Wiring, terminals or connectors
• EBB unit ( HCU and ABS module assembly)

Normal Operation and Fault Conditions

The PSCM calculates steering wheel rotation speed, angle and direction of rotation and sends the information to the ABS module through the GWM over the HS-CAN2 . A failure of the HS-CAN2 , the PSCM or the internal sensors causes the ABS module to set one or more Diagnostic Trouble Codes (DTCs) and the ABS warning indicator is illuminated.

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Incorrectly mounted RCM
• Network communication concern
• Incomplete or incorrect stability control sensor calibration
• Wheels and tires
• Front suspension components
• Steering system components
• RCM
• PSCM

Normal Operation and Fault Conditions

On certain 4x4 vehicles, the ATCM is used to activate and deactivate the selectable drive mode feature. When the driver presses or rotates the ATCM drive mode switch, the ATCM sends a drive mode message out on the HS-CAN2 . When the ABS module receives this message, it takes the necessary action depending on the selectable drive mode message.

On 4x2 vehicles and certain 4x4 vehicles, the selectable drive mode switch in the instrument panel console switch assembly is used to activate and deactivate the selectable drive mode feature. When the driver presses the selectable drive mode switch, the FCIM receives a ground signal over a dedicated circuit. The FCIM sends a drive mode message to the GWM over the HS-CAN3 , the GWM relays this message to the ABS module over the HS-CAN2 . The ABS module takes the necessary action depending on the selectable drive mode message.

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Fuses
• Wiring, terminals or connectors
• Insturment panel console switch assembly (if equipped)
• ATCM (if equipped)
• FCIM

Visual Inspection and Pre-checks

• Make sure BCM fuse 18 (7.5A) for the ATCM is OK

Normal Operation and Fault Conditions

The BCM is programmed with vehicle tire size information during the module configuration step. The BCM shares tire size information with other module over the HS-CAN1 through the GWM . When this DTC sets, the ABS module sends a message to the IPC to illuminate the ABS warning indicator.

REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description (206-09 Anti-Lock Brake System (ABS) and Stability Control, Description and Operation).

DTC Fault Trigger Conditions

Possible Sources

• Temporary or mini-spare tire in use
• Under inflated tires
• Mismatched sized wheels and tires
• Network communication concern
• Incorrect BCM configuration