Operation CHARM: Car repair manuals for everyone.

Generator Noise Test

DIAGNOSIS
^ Noise from a generator may be caused by a loose drive pulley, loose mounting bolts, worn or dirty bearings, defective diode or defective stator. Refer to Charging System Check. System Check - Charging
^ For diagnosis of the PCM controlled generator, refer to PCM Controlled Generator Diagnosis in Computers and Control Systems Testing.

CAUTION: Before removing or installing any electrical unit, or when a tool or equipment could easily come in contact with "live" or "hot all the times" exposed electrical terminals, disconnect the negative battery cable to help prevent personal injury and/or damage to the vehicle or components. Unless instructed otherwise, the ignition switch must be in the OFF or LOCK position.

^ In order to avoid damage to electrical equipment, always observe the following precautions:
^ Do not reverse the connections to the generator.
^ Do not short across or ground any of the terminals in the charging circuit, accept as instructed by the instructions.
^ Never operate the generator with the output terminal disconnected.
^ Before connecting a charger or a booster battery to the vehicle battery. Refer to Jump Starting In Case of Emergency With Auxiliary ( Booster) Battery. Service and Repair
^ Trouble in the charging system will show up as one or more of the following conditions:
^ A faulty indicator lamp operation. Some vehicles have a voltmeter instead of an indicator lamp. The needle on the voltmeter indicates system voltage.
^ The needle stays at either end of the gage, indicating that there may be a defect in the charging system.
^ An undercharged battery, as shown by slow cranking or a dark hydrometer in the battery.
^ An overcharged battery, as shown by leaking electrolyte from the vents.