1993 Acura Integra GS-RFACTORY OEM SERVICE PROCEDURE

Alternator Fr Signal

  1. Connect ECM test harness between ECM and ECM connectors. Unplug connector "D" from main wire harness only. DO NOT  disconnect from ECM. Turn ignition on. Measure voltage between terminals D9 (positive) and A26 (negative). See Figure . If voltage is not about 5 volts, substitute a known good ECM and recheck.
  2. If voltage is about 5 volts, turn ignition off. Reconnect connector "D" to main harness. Start and warm engine to operating temperature. Measure voltage between ECM terminals D94 (positive) and A26.
  3. Turn headlights and rear defogger on. If voltage does not decrease, go to next step. If voltage decreases, alternator FR signal is okay. Remove alternator sensor fuse for 10 seconds to reset ECM.
  4. Turn ignition off. Unplug connector "D" from ECM only. Disconnect negative battery cable. Check for continuity between ECM test harness terminal D9 and ground. If no continuity exists, go to step 6. If continuity exists, unplug Green connector from alternator.
  5. Check again for continuity between ECM test harness terminal D9 and ground. If continuity does not exist, check alternator for possible failure. If continuity is present, repair Blue wire between alternator and ECM terminal D9.
  6. Connect Blue wire to body ground. Check for continuity between ECM terminal D9 and ground. If continuity exist, service alternator. If continuity does not exist, repair Blue wire between alternator and ECM terminal D9.
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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