'00-05 models
- Disconnect the alternator 4P connector.
- Start the engine, and turn on the headlights to high beam.
- Measure the voltage between alternator 4P connector terminal No. 2 and the positive terminal of the battery.Fig 1: Measuring Voltage Between Alternator 4P Connector Terminal 2 And Positive Terminal Of Battery
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there less than 1 V?
YES -Go to step 7.
NO -Go to step 4.
- Turn off the headlights, and turn the ignition switch to LOCK (0).
- Disconnect engine control module (ECM) connector C (31P).
- Check for continuity between ECM connector terminal C2 and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Repair short to ground in the wire between alternator 4P connector terminal No. 2 and ECM connector terminal C2.
NO -Check for loose or poor connections at ECM connector C (31P). If the connection is OK, substitute a known-good ECM (see SUBSTITUTING THE ECM ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ).
- Turn off the headlights, and turn the ignition switch to LOCK (0).
- Disconnect ECM connector C (31P).
- Check for continuity between ECM connector terminal C2 and alternator 4P connector terminal No. 2.Fig 3: Checking Continuity Between ECM Connector Terminal C2 And Alternator 4P Connector Terminal No. 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Replace the alternator (see ALTERNATOR REMOVAL AND INSTALLATION ) or repair the alternator (see ALTERNATOR OVERHAUL ).
NO -Repair open in the wire between alternator 4P connector terminal No. 2 and ECM connector terminal C2.