Symptom Related Diagnostic Procedures

1. Charging warning light does not go on when the ignition switch is turned to ON, before the engine starts.
- Check the bulb.

2. Charging warning light does not switch off after the engine starts.
- Check the voltage regulator inside the generator

3. Discharged or overcharged battery.
- Check the voltage regulator inside the generator.

4. The charging warning light illuminates dimly.
- Check the diode (inside the combination meter) for a short-circuit.

The charging system troubleshooting guide is shown in the following chart.

STEP 1.

Q: Is the battery in good condition? (Refer to Battery - On-vehicle Service - Battery Check.)

YES: Go to Step 2.

NO: Charge or replace the battery.

STEP 2.

Q: Is the generator drive belt in good condition? (Refer to Maintenance Service - Drive Belts.)

YES: Go to Step 3.

NO: Adjust the belt tension or replace the belt.

STEP 3.

Q: Does the charging warning light brightly when the ignition switch is turned on?

YES: Go to step 4.

NO:
- Check the ignition switch. (Refer to Ignition switch.)
- Check for burnt-out charging warning light.
- Check the generator. (Refer to Generator - Disassembly and assembly - Inspection.)
- Check the charging warning light-related circuits.

STEP 4.

Q: Does the charging warning light go out after starting the engine?

YES: Go to step 5.

NO: Check the generator (Refer to Generator - Disassembly and assembly - Inspection.)

STEP 5.

Q: Is an oscilloscope available?

YES: Go to step 8.

NO: Go To Step 7.

STEP 6.

Q: Does the oscilloscope show a normal wave pattern?
(Refer to Charging system - Wave pattern check using a oscilloscope.)

YES:Go to step 7.

NO: Check the generator. (Refer to Generator - Disassembly and assembly - Inspection.)

STEP 7.
- Engine: 2,500 r/min
- Headlight: ON (high beam)
- Voltage between generator terminal B and the positive battery terminal
OK: 0.5 V or less
- Voltage between the negative battery terminal and generator body
OK: 0.5 V or less

Q: Are the generator output line and ground line in good condition?

YES: Go to step 8.

NO: Check the generator output line and ground line.

STEP 8.

Q: Is the output current normal? (Refer to Charging system - On vehicle service - Output current test.)

YES: Go to Step 9.

NO: Check the generator (Refer to Generator - Disassembly and assembly - Inspection.)

STEP 9.

Q: Is the regulated voltage normal? (Refer to Charging system - On vehicle service - Regulated voltage test.)

YES: Go to Step 10.

NO: Check the generator (Refer to Generator - Disassembly and assembly - Inspection.)

STEP 10.

Q: Is the voltage drops in the generator output line normal?

YES: Generator is normal. Check other systems.

NO: Check the output line.