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Theft Warning System Tests (Probe)

NOTE: In all of the following tests, ignition key should always be in OFF position unless otherwise specified in a specific test.
  1. With ignition key off, check 15-amp fuse in passenger compartment fuse panel. If fuse is blown, go to next step. If fuse is okay, go to step 3).
  2. Replace fuse. If fuse blows again, repair short to ground in anti-theft fuse circuit. If fuse does not fail, go to next step.
  3. Disconnect CPU from top of interior fuse panel located at left side kick panel. Using a voltmeter, measure voltage at pin "C" of 16-pin CPU connector. If voltage is more than 10 volts, go to next step. If voltage is less than 10 volts, replace interior fuse panel.
  4. Disconnect CPU from fuse panel. Measure resistance between pin "D" of 16-pin fuse panel connector and ground. If resistance is less than 5 ohms, replace CPU. If resistance is more than 5 ohms, go to next step.
  5. Disconnect 16-pin fuse panel connector. Measure resistance of Black wire between connector and ground. If resistance is less than 5 ohms, replace fuse panel. If resistance is more than 5 ohms, repair Black wire.
  6. Disconnect 20-pin connector from CPU. Apply ground to Light Green wire at CPU connector. If Anti-Theft indicator lights, replace CPU. If light does not light go to next step.
  7. Disconnect 16-pin instrument panel cluster connector. Using a voltmeter, measure voltage of Black/Red wire at connector. If voltage is more than 10 volts, go to next step. If voltage is less than 10 volts, repair Black/Red wire.
  8. Reconnect 16-pin instrument panel cluster connector. Remove anti-theft indicator bulb from cluster. Measure voltage at bulb terminal on instrument panel printed circuit board. If voltage is more than 10 volts, go to next step. If voltage is less than 10 volts, replace printed circuit board.
  9. Disconnect 16-pin instrument panel cluster connector and 20-pin CPU connector. Measure resistance of Light Green wire between 20-pin connector and ground. Resistance should be less than 5 ohms between 20-pin CPU connector and 16-pin cluster connector, and more than 10,000 ohms between 20-pin CPU connector and ground. If resistance readings are correct and warning indicator light is off, go to next step. If resistance readings are correct but warning indicator is on, replace CPU. If resistance readings are incorrect, repair Light Green wire.
  10. Reconnect 16-pin instrument panel cluster connector and disconnect 20-pin CPU connector. Remove anti-theft indicator bulb. Measure resistance between bulb terminal on printed cluster and Light Green wire at 20-pin CPU connector. Measure resistance of Light Green wire between 20-pin connector and ground. Resistance should be less than 5 ohms between 20-pin CPU connector and printed circuit bulb terminal, and more than 10,000 ohms between 20-pin CPU connector and ground. If resistance readings are correct, replace anti-theft indicator bulb. If resistance readings are incorrect, repair printed circuit board.
  11. Disconnect starter interrupt relay from main fuse panel and 20-pin connector from CPU. Measure resistance of Light Green/Yellow wire between relay connector and CPU connector. Measure resistance of Light Green/Yellow wire between CPU connector and ground. If resistance is less than 5 ohms between starter relay connector and CPU connector and more than 10,000 ohms between CPU connector and ground, replace CPU. If resistance is not as indicated, repair Light Green/Yellow wire.
  12. Disconnect 20-pin connector from CPU and flasher module connector. Measure resistance of Green/Red wire between CPU connector and flasher connector. If resistance is less than 5 ohms, replace CPU. If resistance is more than 5 ohms, repair Green/Red wire.
  13. Disconnect 20-pin connector from CPU and horn relay from main fuse panel. Measure resistance of Green/Orange wire between CPU connector and horn relay connector. If resistance is less than 5 ohms, replace CPU. If resistance is more than 5 ohms, repair Green/Orange wire.
  14. Disconnect 20-pin connector from CPU and headlight relay from main fuse panel. Measure resistance of White/Red wire between CPU connector and headlight relay connector. If resistance is less than 5 ohms, replace CPU. If resistance is more than 5 ohms, repair White/Red wire.
  15. Disconnect 20-pin connector from CPU and both door power door lock motor switch connectors. Measure resistance of Brown/Yellow wire between CPU connector and left door switch connector, and Yellow wire between CPU connector and right door switch connector. Measure resistance of Brown/Yellow wire and Yellow wire between CPU connector and ground. Resistance should be less than 5 ohms between CPU connector and door lock motor switch connectors, and more than 10,000 ohms between CPU connector and ground. If resistance is correct but system cannot be armed, go to step 17). If resistance is correct but alarm does not activate, go to step 16). If resistance is correct but alarm is always on, go to step 19). If resistances are incorrect, repair wire(s) in question.
  16. Disconnect both power door lock motor switch connectors. Measure resistance of Black wires between each motor switch connector and ground. Resistance should be less than 5 ohms. If resistance is less than 5 ohms, go to next step. If resistance is more than 5 ohms, repair Black wire(s) in question.
  17. Reconnect both power door lock motor switch connectors. Disconnect 20-pin CPU connector. Unlock doors manually. Measure resistance of Brown/Yellow wire between CPU connector and ground. Measure resistance of Yellow wire between CPU connector and ground. Lock doors manually. Measure resistance of Brown/Yellow wire between CPU connector and ground. Measure resistance of Yellow wire between CPU connector and ground. If there is continuity with doors unlocked, and more than 10,000 ohms resistance with doors locked, replace CPU. If there is no continuity with doors unlocked, or less than 10,000 ohms resistance with doors locked, replace power door lock motor(s).
  18. Disconnect 20-pin connector from CPU and trunk light switch connector. Measure resistance of Red wire between CPU connector and light switch connector. If resistance is less than 5 ohms, replace CPU. If resistance is more than 5 ohms, repair Red wire.
  19. Disconnect 20-pin connector from CPU. Open hood. Measure resistance of Brown/White wire between CPU connector and ground. Close hood. Measure resistance again. Resistance should be less than 5 ohms with hood opened and more than 10,000 ohms with hood closed. If resistance is correct, but alarm does not trigger, replace CPU. If resistance is correct, but alarm is always on, go to step 25). If resistance is incorrect, repair Brown/White wire.
  20. Disconnect 20-pin CPU connector and hood switch connector. Measure resistance of Brown/White wire between CPU connector and hood switch connector. Measure resistance of Brown/White wire between CPU connector and ground. Resistance should be less than 5 ohms between CPU connector and hood switch and more than 10,000 ohms between CPU connector and ground. If resistance is correct, go to step 21). If resistance is not correct, repair Brown/White wire.
  21. Disconnect hood switch connector. Measure resistance of Black wire between hood switch connector and ground. If resistance is less than 5 ohms, replace hood switch. If resistance is more than 5 ohms, repair Black wire.
  22. Disconnect 20-pin connector from CPU. Place key in driver's door lock in unlock position. Measure resistance of Yellow/Red wire between CPU connector and ground. Remove key from lock. Measure resistance of Yellow/Red wire between CPU connector and ground. Repeat procedure for passenger door lock. If resistance is less than 5 ohms with key in unlock position and more than 10,000 ohms with key removed, replace CPU. If resistance is not as indicated, go to next step.
  23. Disconnect 20-pin connector from CPU, both door key cylinder switch connectors and remote entry module connector No. 2 (if equipped). Measure resistance of Yellow/Red wires between CPU connector and key cylinder switch connectors. Measure resistance of Yellow/Red wire between CPU connector and ground. If resistance is less than 5 ohms between CPU connector and key cylinder switch connectors, and more than 10,000 ohms between CPU connector and ground, go to next step. If resistance is not as indicated, repair Yellow/Red wire(s).
  24. Disconnect both door key cylinder connectors. Measure resistance of Black wire between connectors and ground. If resistance readings are less than 5 ohms, replace key cylinder switch(es). If resistance readings are more than 5 ohms, repair Black wire(s).
  25. Disconnect 20-pin CPU connector. Place key in liftgate lock cylinder in unlock position. Measure resistance of Light Green/Red wire between CPU connector and ground. Remove key. Measure resistance again. If resistance is less than 5 ohms with key in unlock position and more than 10,000 ohms with key removed, replace CPU. If resistances are not as indicated go to next step.
  26. Disconnect 20-pin CPU connector and liftgate key cylinder switch connector. Measure resistance of Light Green/Red wire between CPU connector and switch connector. Measure resistance of Light Green/Red wire between CPU connector and ground. If resistance is less than 5 ohms between CPU and switch connector and more than 10,000 ohms between CPU and ground, go to next step. If resistance is not as specified, repair Light Green/Red wire.
  27. Disconnect liftgate key cylinder switch connector. Measure resistance of Black wire between key switch and ground. If resistance is less than 5 ohms, replace key cylinder switch. If resistance is more than 5 ohms, repair Black wire.
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