Trouble Shooting

WARNING: This page is about a different car, the 1995 Jeep Grand Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: If PCM has been replaced, VTA system and self-test will be inoperative until PCM has recorded 20 engine starts.

NOTE: To prevent delays in self-diagnostics caused by illuminated entry timer module, remove illuminated entry timer module, located in relay center under glove box. See Figure in TEST 1A.

System operation may be verified by entering self-test mode. To enter self-test, cycle ignition switch to ACC position 3 times and leave in ACC position.
When self-test is entered, headlights, parking lights and taillights will begin flashing. The horn will sound twice. This verifies light and horn operation.
Turning ignition switch to OFF position will stop lights from flashing and allow system to remain in self-test mode. In self-test mode, a horn pulse should occur at each step to indicate correct operation of related switch and circuit. Allow a one second delay before opening or closing any door or switch.
- Close all doors. Open and close each door individually. There must be a one second delay between opening and closing of doors. The horn should sound when door jam switch opens and again when it closes.
- Open and close hood. Horn should sound when hood is opened and again when it's closed.
- Activate power door locks in both LOCK and UNLOCK directions. Horn should sound after each activation.
- Use key to turn each door lock to unlocked position. Horn should sound when door is unlocked and again when it's locked. There must be a one second delay between locking and unlocking.
- Activate remote keyless entry in both lock and unlock direction. Horn should sound after each activation.
- Turn ignition switch to RUN position. Horn should sound once to indicate correct ignition input. This will also take VTA system module out of self-test mode.
If horn does not sound as indicated, check for continuity at related switch. If switch is okay, check for an open or short in wire harness between VTA system module and switch. If wiring harness is okay, check if Powertrain Control Module (PCM) has been replaced recently. It requires 20 ignition switch cycles (starts) to normalize VTA system operation. During this normalizing period VTA system will function normally except engine will not be prevented from running.