Charging System Indicator Circuit Troubleshooting

Turn the ignition switch ON (II).
1. Does the charging system indicator come on?
2. YES - Go to step 2.
3. NO - Go to step 11.
Start the engine. Hold the engine speed at 2,000 rpm for 1 minute.
1. Does the charging system indicator go off?
2. YES - Charging system indicator circuit is OK. Go to the alternator and regulator circuit troubleshooting (see ALTERNATOR AND REGULATOR CIRCUIT TROUBLESHOOTING ).
3. NO - Go to step 3.
Do the gauge control module self-diagnostic function procedure (see SELF-DIAGNOSTIC FUNCTION ).
1. Does the charging system indicator flash?
2. YES - Go to step 4.
3. NO - Replace the gauge control module.
Turn the ignition switch OFF.
Disconnect the alternator 4P connector.
Turn the ignition switch ON (II).
NOTE: The charging system indicator may come on and then go off.
1. Does the charging system indicator go off?
2. YES - Replace the alternator (see ALTERNATOR REMOVAL AND INSTALLATION ) or repair the alternator (see ALTERNATOR OVERHAUL ).
3. NO - Go to step 7.
Turn the ignition switch OFF.
Connect the Honda Diagnostic System (HDS) to the data link connector (DLC). Turn the ignition switch ON (II), and jump the SCS line with the HDS, then turn the ignition switch OFF.
NOTE: This step must be done to protect the powertrain control module (PCM) from damage.
Disconnect PCM connector B (44P).
Check for continuity between PCM connector terminal B42 and body ground.

Fig 1: Checking Continuity Between PCM Connector Terminal B42 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Repair a short to body ground in the wire between the alternator and the PCM.
2. NO - Update the PCM if it does not have the latest software (see PCM UPDATING AND SUBSTITUTION FOR TESTING ), or substitute a known-good PCM (see HOW TO SUBSTITUTE THE PCM ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).
Do the gauge control module self-diagnostic function procedure (see SELF-DIAGNOSTIC FUNCTION ).
1. Does the charging system indicator flash?
2. YES - Go to step 12.
3. NO - Replace the gauge control module.
Turn the ignition switch OFF.
Disconnect the alternator 4P connector.
Connect alternator 4P connector terminal No. 3 and body ground with a jumper wire.

Fig 2: Connecting Alternator 4P Connector Terminal No. 3 And Body Ground With Jumper Wire
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Turn the ignition switch ON (II).
1. Does the charging system indicator come on?
2. YES - Replace the alternator (see ALTERNATOR REMOVAL AND INSTALLATION ) or repair the alternator (see ALTERNATOR OVERHAUL ).
3. NO - Go to step 16.
Turn the ignition switch OFF.
Connect the HDS to the DLC. Turn the ignition switch ON (II), and jump the SCS line with the HDS, then turn the ignition switch OFF.
NOTE: This step must be done to protect the PCM form damage.
Disconnect PCM connector B (44P).
Check for continuity between PCM connector terminal B42 and body ground.

Fig 3: Checking Continuity Between PCM Connector Terminal B42 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Update the PCM if it does not have the latest software (see PCM UPDATING AND SUBSTITUTION FOR TESTING ), or substitute a known-good PCM (see HOW TO SUBSTITUTE THE PCM ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).
2. NO - Repair an open in the wire between the alternator and the PCM