Pinpoint Test A: The Speed Control Is Inoperative
- A1 VERIFY PCM CONFIGURATION
- Enter the following diagnostic mode on the scan tool: Programmable Parameters.
- Verify that the speed control is enabled in the PCM.
- Is the speed control enabled?
- Yes: GO to A2 .
- No: ENABLE the speed control in the PCM using the scan tool programmable parameters menu. TEST the system for normal operation.
- A2 CHECK FOR ABS DTCs
- Review the recorded DTCs from the ABS self-test.
- Are any DTCs recorded?
- Yes: REFER to the VEHICLE DYNAMIC SYSTEMS article. REPAIR all ABS module DTCs and RETEST the speed control.
- No: GO to A3 .
- A3 CHECK FOR PCM DTCs
- Review the recorded DTCs from the PCM self-test.
- Are any DTCs present?
- Yes:
For speed control DTCs, REFER to the DTC CHARTS .
For non-speed control DTCs, REFER to the INTRODUCTION - GASOLINE MODELS article. REPAIR all PCM DTCs and RETEST the speed control.
- No: GO to A4 .
- A4 CHECK THE VEHICLE SPEED
- Check for correct operation of the speedometer.
- Does the speedometer operate correctly?
- Yes: GO to A5 .
- No: REFER to INSTRUMENTATION, MESSAGE CENTER, AND WARNING CHIMES article to continue diagnosis of the speedometer.
- A5 CHECK THE PARK BRAKE
- Monitor the park brake indicator while applying and releasing the of the park brake.
- Does the park brake operate correctly?
- Yes: GO to A6 .
- No: REFER to INSTRUMENTATION, MESSAGE CENTER, AND WARNING CHIMES article to continue diagnosis of the park brake.
- A6 CHECK THE STOPLAMP SWITCH (BOO1 AND BOO2) PIDs
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: PCM DataLogger.
- Monitor the PCM PIDs BOO1 (brake pedal top travel) and BOO2 (brake pedal bottom travel) while applying and releasing the brake pedal as follows:BRAKE PEDAL POSITION CHART
Brake Pedal Position BOO1 PID BOO2 PID Released Off Off Applied lightly On Off Applied firmly On On - Do the PID values agree with the brake pedal position?
- Yes:
If equipped with a floor shift, GO to A7
.
If equipped with a column shift, GO to A8.
- No: Go To PINPOINT TEST B .
- A7 MONITOR THE PCM (TR) PID
- Enter the following diagnostic mode on the scan tool: PCM DataLogger.
- Monitor the PCM transmission range PID (TR).
- Select DRIVE.
- Does the PID value agree with the TR selector lever position?
- Yes: GO to A9.
- No: REFER to AUTOMATIC TRANSAXLE/TRANSMISSION - 6R80 article to continue diagnosis of the digital TR sensor.
- A8 MONITOR THE PRNDL DISPLAY
- Monitor the PRNDL display in the Instrument Cluster (IC).
- Select DRIVE.
- Does the PRNDL display agree with the TR selector lever position?
- Yes: GO to A9 .
- No: REFER to INSTRUMENTATION, MESSAGE CENTER, AND WARNING CHIMES article to continue diagnosis of the PRNDL display.
- A9 CHECK THE SPEED CONTROL SWITCH
- Enter the following diagnostic mode on the scan tool: PCM DataLogger.
- Press each speed control switch while monitoring the speed control switch PID (SCCS).SPEED CONTROL SWITCH AND SCCS PID VALUE CHART
Speed Control Switch SCCS PID Value - NONE Pressed RESUME RESUME OFF Off ON On SET + SET/+ SET - SET/- - Does the PID value agree with the switch position?
- Yes: GO to A10 .
- No:
If only one switch does not display the correct PID value, INSTALL a new speed control switch. REFER to SPEED CONTROL SWITCH . TEST the system for normal operation.
Otherwise, Go To PINPOINT TEST C .
- A10 CHECK FOR CORRECT PCM OPERATION
- Disconnect all the PCM connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the PCM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
- Yes: INSTALL a new PCM. REFER to ELECTRONIC ENGINE CONTROLS article. 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.