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Switch Circuit

  1. Disconnect wiper switch and wiper relay, and check wiring harness continuity. With ignition switch in LOCK or ACC position, check voltage between ground and terminal No. 18 of 20-pin connector. No voltage should exist. With ignition on, battery voltage should exist. If voltage readings are as specified, go to next step. If voltage readings are not as specified, check and repair affected circuit(s).
  2. Check continuity between terminal No. 16 of 20-pin connector and ground. See Figure. If continuity exists, go to next step. If continuity does NOT exist, check and repair affected circuit(s).
  3. Check continuity between terminal No. 8 of 20-pin connector and terminal No. 10 of 10-pin connector. If continuity exists, go to next step. If continuity does NOT exist, check and repair affected circuit(s).
  4. Check continuity between terminal No. 12 of 20-pin connector and terminal No. 4 of 10-pin connector. If continuity exists, go to next step. If continuity does NOT exist, check and repair affected circuit(s).
  5. Check continuity between terminal No. 4 of 20-pin connector and terminal No. 5 of 10-pin connector. If continuity exists, go to next step. If continuity does NOT exist, check and repair affected circuit(s).
  6. Check continuity between terminal No. 14 of 20-pin connector and terminal No. 8 of 10-pin connector. See Figure. If continuity exists, go to next step. If continuity does NOT exist, check and repair affected circuit(s).
  7. Check continuity between terminal No. 6 of 20-pin connector and terminal No. 3 of 10-pin connector. If continuity exists, all switch circuits are okay. If continuity does NOT exist, check and repair affected circuit(s).
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