Alternator fault diagnosis

Cable to alternator loose or corroded.

Charge warning lamp bulb burned out.

Regulator defective.

Break in the wiring between alternator, ignition switch and warning lamp.

Connectors between rectifier plate and voltage regulator not plugged in.

Carbon brushes not resting on the slip ring.

Field winding in alternator burned out.

• Charge.
• Check cable for proper contact; tighten the bolt.
• Replace.
• Check regulator; replace if necessary.
• Investigate with a voltmeter according to the wiring diagram.
• Remove the alternator; replace the connector if necessary.
• Check that the carbon brushes move freely and that they are at least the minimum length (5 mm).
• Replace the rotor.

Carbon brushes worn.

Regulator defective.

Wiring between three-phase alternator and regulator defective.

• Tension the serpentine belt.
• Visually inspect the carbon brushes; replace if necessary.
• Check regulator; replace if necessary.
• Check wiring and contacts; replace the wiring harness if necessary.