Cruise Control - Inoperative/Malfunctioning

CRUISE CONTROL INOPERATIVE/MALFUNCTIONING

DIAGNOSTIC AIDS
Perform the following in order to avoid a misdiagnosis:
- Inspect for proper operation of the brake lamps. Refer to Exterior Lighting Systems Description and Operation in Lighting Systems.
- Electromagnetic interference (EMI) on the vehicle speed sensor signal circuit may cause erratic cruise control operation.

CONDITIONS FOR ENABLING CRUISE CONTROL
- The vehicle speed is greater than 40 km/h (25 mph).
- The vehicle is not in PARK, REVERSE, NEUTRAL, or 1st gear.
- The system voltage is within 12-16 volts.

TEST DESCRIPTION

Steps 1-10:

Steps 11-23:

Steps 24-29:

The numbers below refer to the step numbers on the diagnostic table.
8. This step tests the center high mounted stop lamp (CHMSL) supply voltage/stop lamp supply voltage circuit for an open or for a high resistance between the stop lamp switch and the throttle actuator control (TAC) module.
9. This step tests the cruise control set/coast switch signal circuit for an open or for a high resistance.
10. This step tests the cruise control resume/accel switch signal circuit for an open or for a high resistance.
11. This step tests the ignition 3 voltage circuit for an open, for a short to ground, or for a high resistance.
29. DTCs will set in the powertrain control module (PCM) when you perform this table.