Alternator and Regulator Circuit Troubleshooting

Special Tools Required 

Alternator, Regulator, Battery & Starter tester OTC 3131 Available through the Honda Tool and Equipment Program 888-424-6857

1. Make sure the battery connections are good and the battery is sufficiently charged (see BATTERY ).
2. Connect the alternator, regulator, battery & starter tester (OTC 3131) to the battery as shown.
   Fig 1: Connecting Alternator, Regulator, Battery & Starter Tester (DTC 3131) To Battery

   Courtesy of AMERICAN HONDA MOTOR CO., INC.
3. Start the engine Hold the engine speed at 3,000 rpm with no load (in N or P (A/T model) or neutral (M/T model)) until the radiator fan comes on, then let it idle.
4. Do the CHARGING SYSTEM TEST

   Does the display indicate voltage within 13 5 - 15 1 V and amperage of 87 5 A or more? 

   YES  - Go to step 5.

   NO  - If the voltage is less than 13.5 V, go to ALTERNATOR CONTROL CIRCUIT TROUBLESHOOTING . If the voltage is over 15 1V and amperage is less than 87 5 A, replace the alternator (see ALTERNATOR REMOVAL AND INSTALLATION  ) or repair the alternator (see ALTERNATOR OVERHAUL . )

5. Check the diode condition on the display.

   Does the display indicate GOOD? 

   YES  - The diode is OK Troubleshooting is complete.

   NO  - If the display indicates BAD, replace the alternator (see ALTERNATOR REMOVAL AND INSTALLATION  ) or repair the alternator (see ALTERNATOR OVERHAUL  ), then retest If the display indicates N/A, the diode pattern could not be diagnosed.