Circuit/System Testing
IMPORTANT:
The drive wheels of the vehicle must be raised and the transmission must be placed in drive or first gear. Refer to Lifting and Jacking the Vehicle
.
- Ignition OFF, disconnect the X1 harness connector at the radio.
- Engine ON, drive wheels raised, place the vehicle in drive or first gear. With a scan tool, verify the speedometer value matches the scan tool vehicle speed parameter in the ECM engine data list.
- If the speedometer matches the scan tool vehicle speed parameter, test the vehicle speed signal circuit terminal F2 for a short to voltage, short to ground, or an open/high resistance. If the circuit tests normal, replace the radio.
- If the speedometer does not match the scan tool vehicle speed parameter, refer to Speedometer and/or Odometer Inaccurate or Inoperative .