Inspection and Verification
NOTE:
Refer to DESCRIPTION AND OPERATION , Intelligent Access (IA) with Push Button Start in
ANTI-THEFT - PASSIVE ANTI-THEFT SYSTEM (PATS)
to review the procedures for achieving the various ignition states (ignition in accessory, ignition on, ignition start, ignition off) on vehicles with this feature.
- Verify the customer concern.
- Verify the stoplamp operate correctly by pressing and releasing the brake pedal with the ignition switch in the ON position. If the stoplamp do not operate correctly, refer to EXTERIOR LIGHTING . If the stoplamp operate correctly, proceed to the next step.
- Visually inspect for obvious signs of mechanical or electrical damage.VISUAL INSPECTION CHART
Mechanical Electrical - Base brake system
- Hydraulic Control Unit (HCU)
- Incorrectly inflated tires
- Mismatched wheels or tires on vehicle
- Wheel speed sensor rings
- ABS module
- Battery Junction Box (BJB) fuse(s):
- 9 (40A)
- 12 (20A)
- Smart Junction Box (SJB) fuse(s):
- 34 (5A)
- 35 (10A)
- Stability control sensor cluster
- Stability/traction control switch
- Steering wheel rotation sensor
- Stoplamp switch
- Wheel speed sensors
- Wiring, terminals or connectors
- If the cause is not visually evident, connect the scan tool to the Data Link Connector (DLC).
- If the scan tool does not communicate with the VCM
:
- check the VCM connection to the vehicle.
- check the scan tool connection to the VCM .
- refer to MODULE COMMUNICATIONS NETWORK , No Power To The Scan Tool, to diagnose no power to the scan tool.
- If the scan tool does not communicate with the vehicle:
- verify the ignition key is in the ON position.
- verify the scan tool operation with a known good vehicle.
- refer to MODULE COMMUNICATIONS NETWORK to diagnose no response from the PCM.
- Carry out the network test.
- If the scan tool responds with no communication for one or more modules, refer to MODULE COMMUNICATIONS NETWORK .
- If the network test passes, retrieve and record continuous memory DTCs.
- Clear the continuous DTCs and carry out the self-test diagnostics for the ABS module.
- If the DTCs retrieved are related to the concern, refer to the ABS MODULE DTC CHART or the INSTRUMENT CLUSTER (IC) DTC CHART . For all other DTCs, refer to MULTIFUNCTION ELECTRONIC MODULES .
- If no DTCs related to the concern are retrieved, GO to SYMPTOM CHART .
NOTE:
Make sure to use the latest scan tool software release.
NOTE:
The Vehicle Communication Module (VCM) LED prove out confirms power and ground from the DLC
are provided to the VCM
.