Antitheft and Alarm Systems: Testing and Inspection

WARNING: ON VEHICLES EQUIPPED WITH AIR-BAGS, REFER TO AIRBAGS BEFORE ATTEMPTING ANY STEERING WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE. FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIR-BAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY.

The Vehicle Theft Security System (VTSS) and the Chrysler Collision Detection (CCD) data bus network should be diagnosed using a DRB scan tool and the proper Diagnostic Procedures. The DRB will provide confirmation that the data bus is functional, that the high-line Central Timer Module (CTM) is receiving and sending the proper messages on the data bus, that the CTM is receiving the proper hard-wired inputs and sending the proper hard-wired outputs, and that the Powertrain Control Module (PCM) is receiving the data bus messages from the CTM. Refer to the Vehicle Theft Security System menu item on the DRB scan tool for the procedures.

Relays
The headlamp (or security) relay is taped to the headlamp switch takeout of the instrument panel wire harness, and the horn relay is located in the junction block on the driver side end of the instrument panel. Each of these relays can be tested as described in the following procedure, however the circuits they are used in do vary To test the relay circuits.

WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS, REFER TO AIRBAGS BEFORE ATTEMPTING ANY STEERING WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE. FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY.

Relay Terminals:

Remove the relay as described in the Removal and Installation to perform the following tests:
1. A relay in the de-energized position should have continuity between terminals 87A and 30, and no continuity between terminals 87 and 30. If OK, go to Step 3. If not OK, replace the faulty relay.
2. Resistance between terminals 85 and 86 (electromagnet) should be 75 ± 5 ohms. If OK, go to Step 4. If not OK, replace the faulty relay.
3. Connect a battery to terminals 85 and 86. There should now be continuity between terminals 30 and 87, and no continuity between terminals 87A and 30. If OK, test the relay circuits. If not OK, replace the faulty relay.