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Foglight Relay Ckt Shorted Lo/Open

  1. Inspect fuse No. 24 (15-amp) located in junction block. See Figure and Figure . If fuse is blown, go to next step. If fuse is okay, go to step  4 .
  2. Remove foglight relay from junction box. Using DVOM, measure resistance between relay terminals No. 85 and 86 (component side). Resistance should be 70-80 ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace foglight relay. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  3. 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 C2 connector 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.
  4. 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.
  5. Voltage is assumed to be present at junction block White 3-pin connector C5 terminal No. 3. 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.
  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. 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.
  8. 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.
  9. Using DVOM, measure resistance between ground and terminal No. 86 on foglight relay socket. If resistance is 10 ohms or greater, replace BCM. See BODY CONTROL MODULE  under REMOVAL & INSTALLATION. If resistance is less than 10 ohms, replace junction block. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
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