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Pinpoint Test I: DTCs C1280, C1282, C1516, C1963, C1975, C2770, U0074, U0151 and U0452




Anti-Lock Control

Pinpoint Tests

Pinpoint Test I: DTCs C1280, C1282, C1516, C1963, C1975, C2770, U0074, U0151 and U0452

Refer to Wiring Diagram Set 42, Vehicle Dynamic Systems for schematic and connector information. Diagrams By Number

Normal Operation

The Restraints Control Module (RCM) measures the yaw rate and vehicle acceleration, then sends the signal through a secondary, dedicated Controller Area Network (CAN) bus to the ABS module. The ABS module uses this information for AdvanceTrac(R) and RSC(R) 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 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 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
- Stability control sensor cluster
- ABS module



PINPOINT TEST I: DTCs C1280, C1282, C1516, C1963, C1975, C2770, U0074, U0151 and U0452

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 safety belt buckle/retractor pretensioners or adaptive load limiting retractors or probe the electrical connectors. Failure to follow this instruction may result in the accidental deployment of the safety belt pretensioners or adaptive load limiting retractors which increases the risk of serious 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.

NOTE: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.

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I1 CHECK FOR A HS-CAN COMMUNICATION CONCERN WITH THE RCM


- Connect the scan tool.
- Ignition ON.
- NOTE: The Network Test does not test the dedicated CAN communications between the ABS module and RCM.
- Using the scan tool, carry out the Network Test.
- Does the RCM pass the Network Test?

Yes
GO to I2.

No
REFER to Information Bus to diagnose the High Speed Controller Area Network (HS-CAN) bus.

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I2 CHECK THE DEDICATED CAN CIRCUITS FOR AN OPEN


- Ignition OFF.
- WARNING: Turn the ignition OFF and wait one minute to deplete the backup power supply. Failure to follow this instruction may result in serious personal injury or death in the event of an accidental deployment.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in Restraint Systems.
- Disconnect: ABS Module C135 .
- Disconnect: RCM C310B .
- Measure the resistance between the ABS module C135, harness side and the RCM C310B, harness side as indicated in the following chart:









- Are the resistances less than 5 ohms?

Yes
GO to I3.

No
REPAIR the affected circuits. CLEAR the DTCs. REPEAT the self-test. GO to I10.

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I3 CHECK THE DEDICATED CAN 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 I4.

No
REPAIR the affected circuits. CLEAR the DTCs. REPEAT the self-test. GO to I10.

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I4 CHECK THE DEDICATED CAN 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 I5.

No
REPAIR the affected circuits. CLEAR the DTCs. REPEAT the self-test. GO to I10.

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I5 CHECK THE DEDICATED CAN CIRCUITS FOR A SHORT TO VOLTAGE


- 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 circuits. CLEAR the DTCs. REPEAT the self-test. GO to I10.

No
GO to I6.

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I6 CHECK RCM TERMINATING RESISTOR


- Ignition OFF.
- Prior to reconnecting any previously disconnected SRS 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 C310A and C310B Connector Position Assurance (CPA) lever/lock for correct operation. Refer to RCM in Restraint Systems.
- repair any concerns found.

Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number

- Connect: RCM 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 I7.

No
GO to I8.

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I7 CHECK THE ABS MODULE FOR CORRECT OPERATION


- Prior to reconnecting any previously disconnected SRS 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 C310A and C310B CPA lever/lock for correct operation. Refer to RCM in Restraint 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.

Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number

- Connect: All Previously Disconnected Component(s)/Connector(s) .
- Repower the SRS. Do not prove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in Restraint Systems.
- Enter the following diagnostic mode on the scan tool: Self Test - ABS Module .
- Was DTC U0151 retrieved on-demand during the self-test?

Yes
INSTALL a new ABS module. REFER to Anti-Lock Brake System (ABS) Module Service and Repair. GO to I10.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. GO to I10.

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I8 CONFIRM THE RCM FAULT


NOTE: Make sure all restraint system components, sensor electrical connectors and the RCM electrical connectors are connected before carrying out the self-test. If not, DTCs will be recorded.

- If previously directed to repower the SRS, depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in Restraint Systems.
- Prior to reconnecting any previously disconnected SRS 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 C310A and C310B CPA lever/lock for correct operation. Refer to RCM Removal and Installation in Restraint 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.

Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number

- Connect: All Previously Disconnected Component(s)/Connector(s) .
- Repower the SRS. Do not prove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in Restraint Systems.
- Enter the following diagnostic mode on the scan tool: Self Test - RCM .
- Were DTCs U0028:08 and/or U0028:88 retrieved on-demand during self-test?

Yes
INSTALL a new RCM. REFER to Restraint Systems. GO to I10.

No
In the process of diagnosing the fault, the fault condition has become intermittent.

CHECK for causes of the intermittent fault. ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition frequently. ACTIVATE other systems in the same wire harness. Do not install any new SRS components at this time. SRS components should only be installed when directed to do so in the pinpoint test. GO to I9.

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I9 CHECK FOR AN INTERMITTENT FAULT


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in
Restraint Systems.
- Disconnect RCM C310B and 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.

Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number

- Connect: All Previously Disconnected Component(s)/Connector(s) .
- Repower the SRS. Do not prove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in Restraint Systems.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - RCM .
- Are any RCM DTCs retrieved on-demand during the self-test?

Yes
REFER to the Restraints Control Module (RCM) DTC Chart in Restraint Systems. Diagnostic Trouble Code Tests and Associated Procedures

No
The fault is not present and cannot be recreated at this time. Do not install any new SRS components at this time. SRS components should only be installed when directed to do so in the pinpoint test. GO to I10.

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I10 CHECK FOR ADDITIONAL SRS DTCs


- Ignition OFF.
- WARNING: Turn the ignition OFF and wait one minute to deplete the backup power supply. Failure to follow this instruction may result in serious personal injury or death in the event of an accidental deployment.
- Reconnect all SRS components (if previously disconnected).
- If previously directed to depower the SRS, repower the SRS. Do notprove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering in Restraint Systems.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - Clear All CMDTCs .
- Enter the following diagnostic mode on the scan tool: Self Test - ABS Module .
- Were any DTCs retrieved on-demand from the RCM or ABS module during self-test?

Yes
Do not clear any DTCs until all DTCs have been resolved. GO to the appropriate DTC Chart and/or Restraint Systems for pinpoint test direction. Diagnostic Trouble Code Tests and Associated Procedures

No
CLEAR all CMDTCs. PROVE OUT the SRS. REFER to Supplemental Restraint System (SRS) Depowering and Repowering in Restraint Systems.

Repair is complete. RETURN the vehicle to the customer.

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