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Service Engine Soon Indicator Inoperative

  1. Disconnect Powertrain Control Module (PCM) or Vehicle Control Module (VCM) harness connectors. Turn ignition switch to RUN position. Connect a fused jumper wire between Brown/White wire terminal of PCM or VCM connector and ground. If indicator illuminates, problem is in PCM or VCM. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. If indicator does not illuminate, go to next step.
  2. Remove jumper wire. Using fused jumper wire, backprobe instrument cluster harness connector terminal No. 23 (Brown/White wire) to ground. If indicator lights, repair open in Brown/White wire. If indicator does not light, replace indicator.
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