C1963
Anti-Lock Control
Pinpoint Test P: DTCs C1280, C1282, C1516, C1963, C1975, C2770, U0151 and U0452
Normal Operation
The ABS module uses information received from several sensors (wheel speed sensors, steering wheel rotation sensor, stability/traction control system sensors, etc.) to determine if vehicle stability, traction or roll warrants ESC (Electronic Stability Control) or RSC(R) (Roll Stability Control) interaction. If an event is going to occur, the ABS module adjusts the brake torque at specific wheels and the PCM reduces engine torque to make the vehicle more stable. Once the ABS module has determined that the stability event has been corrected, it returns the brake and engine torque to normal and continues to monitor the vehicle. DTCs set in the ignition cycle can only be cleared by cycling the ignition off and on once the fault has been corrected. The Restraints Control Module (RCM) measures the yaw rate and vehicle acceleration, then sends the signal through a secondary, dedicated Controller Area Network (CAN) to the ABS module. The ABS module uses this information for AdvanceTrac(R) and RSC(R) (Roll Stability Control) system operation. The ABS module also compares this information to information it receives from other sensors (brake pedal input, steering wheel) to determine how valid the information is and to determine if an instability event is about to occur.
The RCM (Restraints Control Module) and the ABS module communicate along circuits VCA23 (BU/WH) and VCA24 (GN/OG). An open circuit or a short to power or ground on any one of these circuits will cause the ABS module to set a DTC. Also, if the RCM (Restraints Control Module) is not mounted in the correct position, with the electrical connector facing the rear of the vehicle, the ABS module will also set DTCs.
a Interactive Vehicle Dynamics
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- RCM (Restraints Control Module)
- ABS module
PINPOINT TEST P : DTCs C1280, C1282, C1516, C1963, C1975, C2770, U0151 and U0452
WARNING: Do not handle, move or change the original horizontal mounting position of the restraints control module (RCM) while the RCM is connected and the ignition switch is ON. Failure to follow this instruction may result in the accidental deployment of the Safety Canopy(R) and cause serious personal injury or death.
WARNING: Never probe the electrical connectors on air bag, Safety Canopy(R) or side air curtain modules. Failure to follow this instruction may result in the accidental deployment of these modules, which increases the risk of serious personal injury or death.
WARNING: Never disassemble or tamper with seat belt deployable components, including pretensioners, load limiters and inflators. Never back probe deployable device electrical connectors. Tampering or back probing may cause an accidental deployment and result in personal injury or death.
NOTICE: Use the Flex Probe Kit for all test connections to prevent damage to the wiring terminals. Do not use standard multi-meter probes.
NOTE:
Supplemental Restraint System (SRS) components should only be disconnected or reconnected when instructed to do so within a pinpoint test step. Failure to follow this instruction may result in incorrect diagnosis of the SRS (Supplemental Restraint System).
NOTE: The SRS (Supplemental Restraint System) must be fully operational and free of faults before releasing the vehicle to the customer.
P1 CHECK FOR A HS-CAN (High Speed Controller Area Network) COMMUNICATION CONCERN WITH THE RCM (Restraints Control Module)
- Connect the scan tool.
- Ignition ON.
- NOTE: The Network Test does not test the dedicated CAN (Controller Area Network) communications between the ABS module and RCM (Restraints Control Module).
Using a scan tool, carry out a Network Test.
Does the RCM (Restraints Control Module) pass the Network Test?
Yes
GO to P2.
No
REFER to Information Bus to diagnose the High Speed Controller Area Network (HS-CAN) bus.
P2 CHECK FOR RCM (Restraints Control Module) DTCs
- Enter the following diagnostic mode on the scan tool: Self Test- RCM (Restraints Control Module).
Are any RCM (Restraints Control Module) DTCs retrieved on-demand self-test?
Yes
REFER to Restraints and Safety Systems &/or Air Bag Systems to diagnose the RCM (Restraints Control Module) DTCs. TEST the system for normal operation.
No
If only one of the following ABS module DTCs C1280, C1282, C1516, C2770 was retrieved, GO to P3.
If more than one ABS module DTC C1280, C1282, C1516, C2770 was retrieved, GO to P7.
For DTCs U0151 and U0452, GO to P7.
For all other DTCs, GO to P3.
P3 CHECK THE ABS MODULE YAW RATE (YAW_RATE_2) PID
- Enter the following diagnostic mode on the scan tool: Data Logger- ABS Module.
- NOTE: The vehicle must be on level ground and at a complete standstill. Any vehicle movement results in false values for this test.
Monitor the YAW_RATE_2 PID.
Is the YAW_RATE_2 PID value between -3.5 and 3.5?
Yes
GO to P4.
No
GO to P12.
P4 CHECK THE ABS MODULE LATERAL ACCELERATION (LAT_ACCL_2) PID
- NOTE: The vehicle must be on level ground and at a complete standstill. Any vehicle movement results in false values for this test.
Monitor the LAT_ACCL_2 PID.
Is the LAT_ACCL_2 PID value between -0.125g and 0.125g?
Yes
GO to P5.
No
GO to P12.
P5 CHECK THE ABS MODULE LONGITUDINAL ACCELERATION (LONG_ACCL) PID
- NOTE: The vehicle must be on level ground and at a complete standstill. Any vehicle movement results in false values for this test.
Monitor the LONG_ACCL PID.
Is the LONG_ACCL PID value between -0.15g and 0.15g?
Yes
GO to P6.
No
GO to P12.
P6 CHECK THE ABS MODULE ROLL RATE (ROLLRAT) PID
NOTE: The vehicle must be on level ground and at a complete standstill. Any vehicle movement will result in false values for this test.
- Monitor the ROLLRAT PID.
Is the ROLLRAT PID value between -3.5 and 3.5?
Yes
GO to P7.
No
GO to P12.
P7 CHECK THE DEDICATED CAN (Controller Area Network) CIRCUITS FOR AN OPEN
- Ignition OFF.
- Depower the SRS (Supplemental Restraint System). Refer to Supplemental Restraint System (SRS) Depowering and Repowering in Restraints and Safety Systems &/or Air Bag Systems.
- Disconnect: ABS Module C135.
- Disconnect: RCM (Restraints Control Module) C310A and C310B.
- Measure the resistance between the ABS module C135, harness side and the RCM (Restraints Control Module) C310B, harness side as indicated in the following chart:
ABS Module Circuit RCM (Restraints Control Module) C135-37 VCA23 (BU/WH) C310B-20 C135-24 VCA24 (GN/OG) C310B-19
Are the resistances less than 5 ohms?
Yes
GO to P8.
No
REPAIR the affected circuit(s). REPOWER the SRS (Supplemental Restraint System). REFER to Supplemental Restraint System (SRS) Depowering and Repowering in Restraints and Safety Systems &/or Air Bag Systems. CLEAR all CMDTCs. PERFORM a road test. REPEAT the self-test.
P8 CHECK THE DEDICATED CAN (Controller Area Network) CIRCUITS FOR A SHORT TO GROUND
- Measure the resistance between ground and:
- ABS module C135-24, circuit VCA24 (GN/OG), harness side.
- ABS module C135-37, circuit VCA23 (BU/WH), harness side.
Is the resistance greater than 10,000 ohms?
Yes
GO to P9.
No
REPAIR the affected circuit(s). REPOWER the SRS (Supplemental Restraint System). REFER to Supplemental Restraint System (SRS) Depowering and Repowering in Restraints and Safety Systems &/or Air Bag Systems. CLEAR all CMDTCs (Continuous Memory Diagnostic Trouble Codes). PERFORM a road test. REPEAT the self test.
P9 CHECK THE DEDICATED CAN (Controller Area Network) CIRCUITS FOR A SHORT TOGETHER
- Measure the resistance between ABS module C135-24, circuit VCA24 (GN/OG), harness side and ABS module C135-37, circuit VCA23 (BU/WH), harness side.
Is the resistance greater than 10,000 ohms?
Yes
GO to P10.
No
REPAIR the affected circuit(s). REPOWER the SRS (Supplemental Restraint System). REFER to Supplemental Restraint System (SRS) Depowering and Repowering in Restraints and Safety Systems &/or Air Bag Systems. CLEAR all CMDTCs (Continuous Memory Diagnostic Trouble Codes). PERFORM a road test. REPEAT the self test.
P10 CHECK THE DEDICATED CAN (Controller Area Network) CIRCUITS FOR A SHORT TO VOLTAGE
- Repower the SRS (Supplemental Restraint System). Do not prove out the SRS (Supplemental Restraint System) at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in Restraints and Safety Systems &/or Air Bag Systems.
- Ignition ON.
- Measure the voltage between ground and:
- ABS module C135-24, circuit VCA24 (GN/OG), harness side.
- ABS module C135-37, circuit VCA23 (BU/WH), harness side.
Is any voltage present?
Yes
REPAIR the affected circuit(s). CLEAR all CMDTCs (Continuous Memory Diagnostic Trouble Codes). PERFORM a road test. REPEAT the self test.
No
GO to P11.
P11 CHECK RCM (Restraints Control Module) TERMINATING RESISTOR
- Ignition OFF.
- Depower the SRS (Supplemental Restraint System). Refer to Supplemental Restraint System (SRS) Depowering and Repowering in Restraints and Safety Systems &/or Air Bag Systems.
- Prior to reconnecting any previously disconnected SRS (Supplemental Restraint System) component:
- inspect connector(s) (including any in-line connectors) for pushed-out, loose or spread terminals and loose or frayed wire connections at terminals.
- inspect wire harness for any damage, pinched, cut or pierced wires.
- inspect RCM (Restraints Control Module) C310A and C310B Connector Position Assurance (CPA) lever/lock for correct operation. Refer to RCM (Restraints Control Module) in Restraints and Safety Systems &/or Air Bag Systems.
- repair any concerns found.
- Connect: RCM (Restraints Control Module) C310A and C310B.
- Measure the resistance between ABS module C135-37, circuit VCA23 (BU/WH), harness side and C135-24, circuit VCA24 (GN/OG), harness side.
Is the resistance between 108 and 132 ohms?
Yes
GO to P12.
No
INSTALL a new RCM (Restraints Control Module). CLEAR all CMDTCs (Continuous Memory Diagnostic Trouble Codes). PERFORM a road test. REPEAT the self test. If the concern is still present, GO to P14. If other DTCs are present, REFER to the appropriate DTC chart.
P12 CHECK THE RCM (Restraints Control Module) INSTALLATION AND MOUNTING SURFACE
- Ignition OFF.
- If not previously directed to do so, depower the Supplemental Restraint System (SRS). Refer to Supplemental Restraint System (SRS) Depowering and Repowering in Restraints and Safety Systems &/or Air Bag Systems.
- Inspect the Restraints Control Module (RCM) installation and make sure that the fasteners are fully seated and tightened correctly. Refer to RCM (Restraints Control Module) in Restraints and Safety Systems &/or Air Bag Systems.
- Inspect the mounting surface for damage, corrosion or foreign material.
Is the RCM (Restraints Control Module) installed correctly and is the mounting surface clean and free from damage?
Yes
GO to P13.
No
REPAIR or INSTALL new as necessary. REPOWER the SRS (Supplemental Restraint System). REFER to Supplemental Restraint System (SRS) Depowering and Repowering in Restraints and Safety Systems &/or Air Bag Systems. CLEAR all CMDTCs (Continuous Memory Diagnostic Trouble Codes). PERFORM a road test.
REPEAT the self test.
P13 CHECK FOR AN INTERMITTENT FAULT
- Disconnect: RCM (Restraints Control Module) C310A and C310B.
- Disconnect: ABS module C135.
- inspect connector(s) (including any in-line connectors) for corrosion, loose or spread terminals and loose or frayed wire connections at terminals.
- inspect wire harness for any damage, pinched, cut or pierced wires.
- repair any concerns found.
- Connect: All Previously Disconnected Component(s)/Connector(s).
- Repower the SRS (Supplemental Restraint System). Do not prove out the SRS (Supplemental Restraint System) at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in Restraints and Safety Systems &/or Air Bag Systems.
- Perform a road test.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test- ABS Module.
Is the concern still present?
Yes
INSTALL a new RCM (Restraints Control Module). CLEAR all CMDTCs (Continuous Memory Diagnostic Trouble Codes). PERFORM a road test. REPEAT the self test. If the concern is still present, GO to P14. If other DTCs are present, REFER to the appropriate DTC chart.
No
The fault is not present and cannot be recreated at this time. Do not install any new SRS (Supplemental Restraint System) components at this time. SRS (Supplemental Restraint System) components should only be installed when directed to do so in the pinpoint test.
P14 CHECK THE ABS MODULE FOR CORRECT OPERATION
- Depower the SRS (Supplemental Restraint System). Refer to Supplemental Restraint System (SRS) Depowering and Repowering in Restraints and Safety Systems &/or Air Bag Systems.
- Prior to reconnecting any previously disconnected SRS (Supplemental Restraint System) component:
- inspect connector(s) (including any in-line connectors) for pushed-out, loose or spread terminals and loose or frayed wire connections at terminals.
- inspect wire harness for any damage, pinched, cut or pierced wires.
- inspect RCM (Restraints Control Module) C310A and C310B CPA (Connector Position Assurance) lever/lock for correct operation. Refer to RCM (Restraints Control Module) in Restraints and Safety Systems &/or Air Bag Systems.
- inspect ABS module C135 for dirt, corrosion, water intrusion, pushed-out, loose or spread terminals and loose or frayed wire connections at terminals.
- repair any concerns found..
- Connect: All Previously Disconnected Component(s)/Connector(s).
- Repower the SRS (Supplemental Restraint System). Do not prove out the SRS (Supplemental Restraint System) at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in Restraints and Safety Systems &/or Air Bag Systems.
- Perform a road test.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test- ABS Module.
Is the concern still present?
Yes
INSTALL a new ABS module. REFER to Anti-Lock Brake System (ABS) Module .
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.