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Foglight Relay Ckt Shorted Lo/Open

  1. Ensure foglight relay is present in junction block. See Figure. If foglight relay is not present, install relay. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS. If relay is present, go to next step.
  2. Inspect fuse No. 24 (15-amp) located in junction block. If fuse is blown, go to next step. If fuse is okay, go to step  6.
  3. Install a known-good relay in place of existing relay. Recheck system operation. If system does not operate properly, go to next step. If system operates properly, replace defective relay. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  4. Voltage is assumed to be present at junction block White 3-pin connector C5 terminal No. 3. See Figure. Using DVOM, measure voltage between ground and B+ terminal on fuse No. 24 socket. If voltage is greater than 10 volts, go to next step. If voltage is less than 10 volts, replace junction block. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  5. Using DVOM, measure resistance between ground and terminal No. 87 (relay output circuit) on foglight relay socket. See Figure. If resistance is less than 5 ohms, repair short to ground in Light Blue wire between foglights and junction block or internal circuit between junction block connector C2 and foglight relay and replace fuse No. 24. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS. If resistance is 5 ohms or greater, replace fuse No. 24. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  6. Remove foglight relay from junction block. Using DVOM, measure voltage between ground and terminals No. 30 and 86 on foglight relay socket. If voltage is greater than 10 volts on both circuits, go to next step. If voltage is 10 volts or less on either circuit, replace junction block. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  7. Turn ignition on. Using DVOM, measure voltage between ground and B+ terminal on fuse No. 24 socket. If voltage is greater than 10 volts, go to next step. If voltage is less than 10 volts, replace junction block. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  8. Install a known-good relay in junction block. Operate foglights. If foglights do not operate correctly, go to next step. If foglights operate correctly, replace relay. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  9. Turn ignition off. Remove foglight relay. Remove Body Control Module (BCM) from back of junction block. See Figure. Using DVOM, measure resistance between BCM junction block connector terminal No. 2 and terminal No. 86 on foglight relay socket. See Figure. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or greater, replace junction block. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  10. Using DVOM, measure resistance between ground and terminal No. 86 on foglight relay socket. go to next step. If resistance is 10 ohms or greater, If resistance is less than 10 ohms, replace junction block. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  11. Disconnect a foglight bulb connector. Using DVOM, measure resistance of Light Blue wire between foglight bulb connector and terminal No. 87 on foglight relay socket. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or greater, repair open in Light Blue wire between foglights and junction block. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  12. Using scan tool, select INPUT/OUTPUT under BODY. Read FOGLIGHT SWITCH STATE. Turn foglight switch from off to on position while monitoring scan tool. If foglight switch status changes, go to next step. If foglight switch status does not change, go to step  14.
  13. Replace BCM. See BODY CONTROL MODULE  under REMOVAL & INSTALLATION. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  14. Using scan tool, select INPUT/OUTPUTS under BODY. Monitor FOGLIGHT SWITCH STATE. Disconnect left multifunction switch connector. Connect a jumper between terminals No. 1 and 4 on multifunction switch connector. See Fig 1. If FOGLIGHT SWITCH STATE does not change when jumper wire is connected, go to next step. If FOGLIGHT SWITCH STATE changes when jumper wire is connected, replace left multifunction switch. See appropriate STEERING COLUMN SWITCHES article. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  15. Turn ignition off. Disconnect BCM connector C2. Using DVOM, measure resistance between ground and left multifunction switch connector terminal No. 1 (White/Tan wire). If resistance is 5 ohms or greater, go to next step. If resistance is less than 5 ohms, repair short to ground in White/Tan wire between left multifunction switch connector and BCM.
  16. Replace BCM. See BODY CONTROL MODULE  under REMOVAL & INSTALLATION. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
Fig 1: Identifying Left Multifunction Switch Connector Terminals
G99I02159Courtesy of CHRYSLER CORP.
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