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Power door Locks

NOTE: Perform test only if instructed to do so. Before performing any of the tests in this section, the battery must be fully charged.

  1. None Of The Door Locks Work

    Check circuit breaker. Is circuit breaker functional? If yes, go to next step. If no, replace breaker.
  2. Turn key off. Disconnect C418 connector from the module. Turn key to run. Check the voltage between terminal No. 4 of C418 connector and ground while activating lock switch. See Figure and Figure . Is voltage greater than 10 volts? If yes, go to next step. If no, service short in Circuit 517, or charge battery. Repeat Quick Test  . See WIRING DIAGRAMS  .
  3. With system connected and voltmeter connected to terminal No. 13 of the C418 connector and ground. Does meter read 10 volts or more when door lock and unlock switches are activated? If 10 volts or more, go to next step. If under 10 volts caused by blown breaker, check for short to ground in Circuits 163, 118, 117, or shorted lock actuator. See WIRING DIAGRAMS  .
  4. Disconnect module connector C418. Check for continuity between terminal No. 5 of C418 connector and ground. Check for continuity between terminal No. 6 of C418 connector and ground. If continuity exists, go to next step. If no continuity exists, service open in Black wire. Repeat Quick Test  . See WIRING DIAGRAMS  .
  5. Manually lock all doors. Disconnect control module connector C418. Connect a jumper between terminal No. 8 of connector C418 and ground. See Figure . Momentarily connect jumper between terminals No. 14 and 3 of connector C418. Driver's door should unlock. Relock driver's door. Momentarily connect jumper between terminals No. 13 and 1 of connector C418. If all doors unlock, go to next step. If no doors unlock, service 163, 117 or 118 or door lock motor(s). See WIRING DIAGRAMS  . Repeat Quick Test  .
  6. Check for lock switch stuck in LOCK or UNLOCK position. Are switches functional? If no, replace Switch. Repeat Quick Test  . If yes, go to next step.
    NOTE: Switch may be mechanically stuck. Reset using meter.
  7. Disconnect module connector C418. Check for short between terminal No. 10 and ground. Check for short between terminal No. 11 and ground. If no short exists, replace control module. Repeat Quick Test  . If short exists, service short to ground in Circuit 119 or 120. Repeat Quick Test  .

  8. One Or More Locks Do Not Work

    Manually operate door lock several times to check for binding. If no binding present, go to next step. If binding is present, lubricate lock and linkage.
  9. Remove door trim panel. Measure voltage at suspect door lock actuator while pressing door lock switch. If reading is 10 volts or greater go to step  11 . If reading is less than 10 volts, go to next step.
  10. With C418 connector connected, depress lock button and measure voltage at terminals No. 1 and 8 to ground. With lock button released there should be zero volts at terminals No. 1 and 8. If reading is 10 volts or greater when depressed and zero volts when released, service Circuits 163, 117 or 118 for open or short. See WIRING DIAGRAMS  . If reading is under 10 volts when depressed, replace module. Repeat Quick Test  . If reading is more than 10 volts when not depressed, replace module. Repeat Quick Test  .
  11. Check voltage between the lock actuator Circuit 118 and ground while moving door lock switch to UNLOCK position. If reading is 10 volts or greater, replace faulty door lock actuator. If reading is less than 10 volts, service open or short in Circuit 120 or 118. Repeat Quick Test  .

  12. One Or More Switches Do Not Work

    Turn ignition off. Disconnect control module connector C418. Remove door trim panel from door with faulty switch. See POWER DOOR LOCKS, FUEL DOOR RELEASE & TRUNK RELEASE for trim panel removal. Check for continuity between terminal No. 10 of connector C418 and lock side door switch on Pink/Yellow wire. Check continuity between terminal No. 11 of connector C418 and unlock side of door lock switch on Pink/Light Green wire. Check for continuity between door lock switch ground terminal and chassis. If continuity exists, replace door lock switch. If no continuity exists, repair open in Pink/Yellow, Pink/Light Green or Black wire. See WIRING DIAGRAMS  .

  13. Locks Will Only Lock Or Unlock

    Turn ignition off. Disconnect control module connector C418. Check ground to door lock switches (Black) wire. Check for continuity between terminal No. 10 (terminal No. 11 if doors will not unlock) of connector C418 and ground while pushing door lock switch to lock position. See Figure . If continuity exists, go to next step. If circuit is open between terminals No. 10 or 11 and ground, go to step  15 . If black wire is open, repair open. See WIRING DIAGRAMS  .
  14. Reconnect control module connectors. Measure voltage at terminal No. 9 of connector C418 while pushing a door lock switch to lock position. See Figure . Measure voltage at terminal No. 3 of connector C418 while pushing a door lock switch to unlock position. If reading is 10 volts or greater, repair open or short in Pink/Black lock wire or Pink/Orange unlock wire. If voltage is less than 10 volts, replace control module. Repeat Quick Test  .
  15. Check for continuity between Pink/Yellow lock or Pink/Light Green unlock wire terminal of door lock switch and ground while pushing switch to either lock or unlock position. If continuity exists, repair open in Pink/Yellow lock or Pink/Light Green unlock wire. Repeat Quick Test  . If no continuity exists, replace door lock switch. Repeat Quick Test  .

  16. Locks Work Intermittently

    Turn ignition off. Disconnect control module C418 connector. Check for continuity between terminals No. 5 and 6 of connector and ground. If continuity exists, repair loose connections.Repeat Quick Test  . If no continuity exists, repair open in Black wire.

  17. Locks Do Not Work In Freezing Weather

    If door locks do not operate in freezing weather, park vehicle in garage to thaw. Lubricate lock cylinders. If locks operate, go to next step. If locks do not operate, see Quick Test  .

  18. Locks Only Work With Engine Running

    Double check battery state of charge, latch or linkage binding and loose or corroded connector at actuators, switches, and control module connectors. Check locks. repair as necessary. If these are okay, see Quick Test  .
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