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Alternator Signal

  1. Ensure battery is fully charged and that all terminals and connections are fully tight. Turn ignition to RUN position with engine off. The charge indicator light should be on. If indicator light is off, disconnect wiring harness from alternator.
  2. Connect a fused (5-amp.) jumper wire between harness connector terminal "L" and ground. If charge indicator light illuminates, replace alternator.
  3. If charge indicator light does not illuminate, check for open circuit between ignition switch and alternator harness connector. If circuits are okay, check charge indicator light bulb and replace (if necessary).
  4. Start and maintain engine speed at a moderate RPM. The charge indicator light should be off. If light stays on, disconnect wiring harness at alternator. If indicator light turns off, replace alternator. If indicator light stays on, check for shorted harness between connector and indicator light.
  5. Check battery for overcharged or undercharged condition. See UNDERCHARGED OR OVERCHARGED BATTERY test.
CAUTION: DO NOT  ground terminals except as instructed. Avoid operation with battery out of circuit or output terminal open.