Regulator Circuit Troubleshooting
Alternator and Regulator Circuit Troubleshooting1. Make sure the battery is sufficiently charged.
2. Raise the hoist to full height.
3. Hook up the ammeter, 0 - 400 A, to the starter subharness.
4. Lower the hoist.
5. Hook up the voltmeter, 0 - 20 V (accurate within 0.1 V), to T101.
6. Start the engine. Hold the engine at 3,000 rpm with no load (in Park or Neutral) until the radiator fan comes on, then let it idle.
7. Raise the engine speed to 2,000 rpm, and hold it there.
8. Turn the headlights (high beam) on, and measure voltage at the under-hood fuse/relay box terminal.
Is the voltage between 13.9 and 15.1 V?
YES - Go to step 9.
NO - Repair the alternator components
9. Read the amperage at 13.5 V?
NOTE: Adjust the voltage by turning the blower motor, rear window defogger, brake lights, etc ON
Is the amperage 60 A or more?
YES - Alternator/regulator operation is OK Go to Alternator Control Circuit Troubleshooting.
NO - Repair the alternator components