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Wiper Not Working At All

  1. Replace wiper high/low relay in Power Distribution Center (PDC) with a known-good relay. See Figure. turn ignition on. Turn wipers on. If wipers do not operate, go to next step. If wipers operate correctly, replace wiper high/low relay. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  2. Replace wiper on/off relay in Power Distribution Center (PDC) with a known-good relay. If wipers do not operate, go to next step. If wipers operate correctly, replace wiper on/off relay. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  3. Remove wiper on/off relay. Remove junction block circuit breaker No. 1. See Figure. Connect a jumper wire between ground and circuit breaker No. 1 socket fused ignition switch output. Using DVOM, measure resistance between ground and wiper on/off relay socket terminal No. 86 (Dark Blue wire). If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or greater, repair open in Dark Blue wire. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  4. Turn ignition off. Disconnect wiper motor connector. Wiper motor is located under left side of cowl cover. Check for poor connections. Ensure all lights and accessories are off. Using DVOM, measure resistance between ground and wiper motor connector terminal No. 4 (Black wire). See Figure. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or greater, repair open in Black wire between wiper motor and ground. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  5. Ensure wiper on/off relay and junction block No. 1 circuit breaker are removed. Using DVOM, measure resistance between ground and wiper on/off relay socket terminal No. 86 (fused ignition switch output circuit). If resistance is greater than 10 ohms, go to next step. If resistance is less than 10 ohms, repair short to ground in Dark Blue wire. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  6. Turn ignition off. Ensure both wiper relays are removed. Using DVOM, measure resistance of Yellow/Dark Green wire between wiper on/off relay socket terminal No. 30 and wiper high/low relay socket terminal No. 30. If resistance is less than 10 ohms, go to next step. If resistance is 10 ohms or greater, repair open in Yellow/Dark Green wire. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  7. Using DVOM, measure resistance between ground and wiper on/off relay socket terminal No. 30 (Yellow/Dark Green wire). If resistance is 10 ohms or greater, go to next step. If resistance is less than 10 ohms, repair short to ground in Yellow/Dark Green wire. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  8. Disconnect Body Control Module (BCM) connector C1. See Figure. Turn ignition on. Using DVOM, measure voltage between ground and BCM connector C1 terminal No. 22 (Red/Violet wire). See Figure. If voltage is less than one volt, go to next step. If voltage is greater than one volt, repair short to voltage in Red/Violet wire. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  9. Using DVOM, measure resistance between ground and wiper high/low relay socket terminal No. 87A (Brown/White wire). If resistance is 10 ohms or greater, go to next step. If resistance is less than 10 ohms, repair short to ground in Brown/White wire. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  10. Connect a jumper wire between ground and BCM connector C1 terminal No. 22 (Red/Violet wire). Using DVOM, measure resistance between ground and wiper on/off relay socket terminal No. 85. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or greater, repair open in Red/Violet wire. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  11. Using scan tool, read wiper mode switch voltage. Turn wiper switch to LO position. If voltage is not about .82 volt, go to next step. If voltage is about .82 volt, replace BCM. See BODY CONTROL MODULE  under REMOVAL & INSTALLATION. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
  12. Ensure all connectors and components are connected. Disconnect wiper motor connector. Turn wiper switch to LO position. Using DVOM, measure and record voltage between ground and wiper motor connector terminal No. 5 (Brown/White wire). Turn wiper switch to HIGH position. Using DVOM, measure and record voltage between ground and wiper motor connector terminal No. 6 (Red/Yellow wire). If voltage for both circuits is greater than 10 volts, replace wiper motor. See appropriate WIPER/WASHER SYSTEMS article. Perform BODY VERIFICATION TEST  under VERIFICATION TESTS. If voltage is 10 volts or less on either circuit, test is complete.
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