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Diagnosis & Repair (Using OBD-II Scan Tool)

  1. Access ECM behind glove box. Connect Check Harness "A" (SST 09990-01000) to ECM. See TEST PREPARATION under SELF-DIAGNOSTIC SYSTEM in TESTS W/CODES article.
  2. Measure voltage between ground and terminal No. 77 (Gray/Red wire) at ECM "B" connector. Turn ignition switch to START position. With starter being cranked, voltage should be 6 volts or more. If voltage is not as specified, go to next step. If voltage is as specified, no problem is indicated at this time. Diagnose by symptom. See TESTS W/O CODES article.
  3. Check for open in wiring harness between ECM and starter relay. See appropriate wiring diagram in WIRING DIAGRAMS article. Repair as necessary. If wiring is okay, replace ECM and retest.
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