Initial Inspection and Diagnostic Overview
CHARGING SYSTEM DIAGNOSISTROUBLESHOOTING HINTS
- Generator malfunction light dose not go on when the ignition switch is turned to ON, before the engine starts.
- Check the bulb.
- Generator malfunction light dose 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.
- The generator malfunction light illuminates dimly.
- Check the diode (inside the combination meter) for a short-circuit.
TROUBLESHOOTING GUIDE
The charging system troubleshooting guide is shown in the following steps.
STEP 1.
Q: Is the battery in good condition? (Refer to Battery, Battery/Testing and Inspection/Component Tests and General Diagnostics/Component Tests/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 General - Maintenance Service - Drive Belts (For Generator 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 Ignition Switch, Ignition Switch/Testing and Inspection/Component Tests and General Diagnostics/Component Tests/Ignition Switch Continuity Check.
- Check for burnt-out generator malfunction light.
- Check the generator malfunction light-related circuits.
STEP 4.
Q: Does the generator malfunction light go out after starting the engine?
YES: Go to Step 5.
NO: Check the generator malfunction light-related circuits.
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/Testing and Inspection/Component Tests and General Diagnostics/Wave Pattern Check Using an Oscilloscope.)
YES: Go to Step 7.
NO: Check the generator related circuit. If the circuit is normal, replace the generator (Refer to Charging System/Alternator/Service and Repair/Removal and Replacement/Generator Assembly Removal and Installation).
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/Testing and Inspection/Component Tests and General Diagnostics/Output Current Test)
YES: Go to Step 9.
NO: Check the generator related circuit. If the circuit is normal, replace the generator (Refer to Charging System/Alternator/Service and Repair/Removal and Replacement/Generator Assembly Removal and Installation).
STEP 9.
Q: Is the regulated voltage normal? (Refer to Refer to Charging System/Testing and Inspection/Component Tests and General Diagnostics)
YES: Go to Step 10.
NO: Check the generator related circuit. If the circuit is normal, replace the generator (Refer to Charging System/Alternator/Service and Repair/Removal and Replacement/Generator Assembly Removal and Installation).
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.