Erasing Diagnostic Trouble Codes

The scan tool must be used to erase a DTC.

The following procedures may be used to diagnose the charging system if:

• the check gauges lamp or battery lamp is illuminated with the engine running
• the voltmeter (if equipped) does not register properly
• an undercharged or overcharged battery condition occurs.

Remember that an undercharged battery is often caused by:

• accessories being left on with the engine not running
• a faulty or improperly adjusted switch that allows a lamp to stay on. Refer to Ignition-Off Draw Test. Refer to Electrical/Battery System/BATTERY - Standard Procedure
• loose generator belt.