FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.

Charging System Diagnosis

CHARGING SYSTEM DIAGNOSIS

TROUBLESHOOTING HINTS

Generator malfunction light does not go on when the ignition switch is turned to ON, before the engine starts.
- Check the generator malfunction light.

Generator malfunction light does not switch off after the engine starts.
- Check the IC voltage regulator inside the generator.

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

TROUBLESHOOTING GUIDE

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

STEP 1.

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

YES : Go to Step 2.

NO : Charge or replace the battery.

STEP 2.

Q: Is the generator drive belt in good condition? (Refer to General - Maintenance Service - Drive Belts (For Generator, Power Steering Pump and Air Conditioning) (Check)).

YES : Go to Step 3.

NO : Adjust the belt tension or replace the belt.

STEP 3.

Q: Does the generator malfunction light come on when the ignition switch is turned on?

YES : Go to Step 4.

NO : Check the ignition switch. (Refer to Chassis Electrical - Ignition Switch - Ignition Switch - Inspection). Ignition Switch Continuity Check
Check the generator malfunction light and its related circuits.
Check the generator. (Refer to Charging System - Generator Assembly - Inspection).

STEP 4.

Q: Does the generator malfunction light go out after starting the engine?

YES : Go to Step 5.

NO : Check the generator (Refer to Charging System - Generator Assembly - Inspection).

STEP 5.

Q: Is an oscilloscope available?

YES : Go to Step 6.

NO : Go to Step 7.

STEP 6.

Q: Does the oscilloscope show a normal wave pattern? (Refer to Charging System - On-vehicle Service - Wave Pattern Check Using an Oscilloscope). Oscilloscope Patterns and Waveforms

YES : Go to Step 7.

NO : Check the generator. (Refer to Charging System - Generator 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). Output Current Test

YES : Go to Step 9.

NO : Check the generator (Refer to Charging System - Generator Assembly - Inspection).

STEP 9.

Q: Is the regulated voltage normal? (Refer to Charging System - On-vehicle Service - Regulated Voltage Test). Regulated Voltage Test

YES : Go to Step 10.

NO : Check the generator (Refer to Charging System - Generator Assembly - Inspection).

STEP 10.

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

YES : Generator is normal. Check other systems.

NO : Check the output line.