Alternator and Regulator Circuit Troubleshooting

Special Tools Required 

Alternator, Regulator, Battery&Starter tester OTC3131 Available through the Honda Tool and Equipment Program 888-424-6857

1. Remove the engine compartment covers (see ENGINE COMPARTMENT COVER REPLACEMENT )
2. Make sure the battery connections are good, and the battery is sufficiently charged
3. Connect the alternator, regulator, battery&starter tester (OTC3131) to the battery as shown
   Fig 1: Connecting Alternator, Regulator, Battery And Starter Tester (OTC3131) To Battery

   Courtesy of AMERICAN HONDA MOTOR CO., INC.
4. 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
5. Do the CHARGING SYSTEM TEST

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

   YES  -Go to step 6

   NO  -If the voltage is less than 13 5 V, go to alternator control circuit troubleshooting (see 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 )

6. 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

   NOTE: If the display indicates N/A, the diode pattern could not be diagnosed Repeat the test again If N/A appears repeatedly, replace the alternator
7. Install the engine compartment covers (see ENGINE COMPARTMENT COVER REPLACEMENT )