Checking Generator Systems

During normal operation, the generator warning light turns on when the ignition is in the RUN position and turns off when the engine is started. If the lamp does not operate normally or the battery is overcharged or discharged, use the following procedure to diagnose the charging system. Remember that a discharged battery is the result of appliances not turned off at night, faulty lamp switches, trunk lid or glove box.

Check the generator as follows:

1. Inspect the belt and wiring.

2. When the ignition is on and the engine is stopped, the charge indicator lamp should be on. Otherwise, you must disconnect the wiring harness on the generator and ground the contact in this harness "L" with a 5 amp jumper wire.

• If the lamp is on, replace the alternator. follow the paragraph «Generator» Car maintenance of this section.
• If the lamp does not illuminate, look for an open circuit between the ignition switch and the harness connector. The control lamp may burn out.

3. With the ignition on and the engine running at moderate speeds, the charge indicator lamp should be off. Otherwise, the wiring harness must be disconnected at the generator.

• If the lamp goes out, replace the alternator. follow the paragraph «Generator» Car maintenance of this section.
• If the lamp continues to burn, check for a short to ground between the connector and the test lamp.

Important: Always check the generator output power before assuming a generator failure from a short to terminal ground "L". follow the paragraph «Generator» in the Unit Repair section.