Pinpoint Test N: The Traction Control, ESC and RSC(R) Systems Cannot Be Disabled
Anti-Lock Control
Pinpoint Tests
Pinpoint Test N: The Traction Control, ESC and RSC(R) Systems Cannot Be Disabled
Refer to Wiring Diagram Set 42, Vehicle Dynamic Systems for schematic and connector information. Diagrams By Number
Normal Operation
When one or more drive wheels lose traction and begin to spin, the ABS module sends a request to the PCM over the High Speed Controller Area Network (HS-CAN) bus to modulate the engine torque. This is achieved by regulating fuel and spark to the cylinders. At the same time, the ABS module operates the hydraulic pump motor and the appropriate hydraulic valves to actuate the brake calipers and sends a message to the Instrument Cluster (IC) along the HS-CAN bus to flash the stability/traction control indicator "sliding-car icon". The system can be disabled pressing the stability/traction control switch. When the switch is pressed, the ABS receives a voltage signal and will ignore any stability/traction control events until the switch is pressed again or the ignition switch is cycled.
Fused ignition voltage is sent to the stability/traction control switch from Smart Junction Box (SJB) fuse 18 (10A) along circuit CBP18 (GY/OG). When pressed, the switch closes and momentarily connects circuit CBP18 (GY/OG) to circuit CCA15 (YE/GY) sending the voltage to the ABS module along circuit CCA15 (YE/GY). The ABS module sends a message to the IC along the HS-CAN bus to illuminate the stability/traction control indicator.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Stability traction control switch
- ABS module
PINPOINT TEST N: THE TRACTION CONTROL, ESC AND RSC(R) SYSTEMS CANNOT BE DISABLED
NOTICE: Use the Flex Probe Kit for all test connections to prevent damage to the wiring terminals. Do not use standard multi-meter probes.
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N1 CHECK THE VOLTAGE TO THE STABILITY/TRACTION CONTROL SWITCH
- Ignition OFF.
- Disconnect: Stability/Traction Control Switch C280.
- Ignition ON.
- Measure the voltage between stability/traction control switch C280-6, circuit CBP18 (GY/OG), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to N2.
No
VERIFY SJB fuse 18 (10A) is OK. If OK, REPAIR circuit CBP18 (GY/OG). If the fuse is not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. TEST the system for normal operation. Diagrams By Number
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N2 CHECK THE STABILITY TRACTION CONTROL SWITCH
- Measure the resistance between stability/traction control switch C280 pin-1 and pin-6, component side while pressing and releasing the switch.
- Is the resistance less than 5 ohms with the switch pressed and greater than 10,000 ohms with the switch released?
Yes
GO to N3.
No
INSTALL a new stability/traction control switch. REFER to Stability/Traction Control Switch Service and Repair. TEST the system for normal operation.
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N3 CHECK CIRCUIT CCA15 (YE/GY) FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: ABS Module C155.
- Ignition ON.
- Measure the voltage between ABS module C155-4, circuit CCA15 (YE/GY), harness side and ground.
- Is any voltage present?
Yes
REPAIR circuit CCA15 (YE/GY). TEST the system for normal operation.
No
GO to N4.
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N4 CHECK CIRCUIT CCA15 (YE/GY) FOR A SHORT TO GROUND
- Ignition OFF.
- Measure the resistance between ABS module C155-4, circuit CCA15 (YE/GY), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to N5.
No
REPAIR circuit CCA15 (YE/GY). TEST the system for normal operation.
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N5 CHECK CIRCUIT CCA15 (YE/GY) FOR AN OPEN
- Measure the resistance between ABS module C155-4, circuit CCA15 (YE/GY), harness side and stability/traction control switch C280-1, circuit CCA15 (YE/GY), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to N6.
No
REPAIR circuit CCA15 (YE/GY). TEST the system for normal operation.
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N6 CHECK FOR CORRECT ABS MODULE OPERATION
- Check ABS module C155 for:
- corrosion.
- pushed-out pins.
- spread terminals.
- Connect: ABS Module C155.
- Make sure the connector seats correctly, then operate the system and verify the concern is still present.
- Is the concern still present?
Yes
INSTALL a new ABS module. REFER to Anti-Lock Brake System (ABS) Module Service and Repair. TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.
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