Cummins/Onan DL3 — Battery Charging Checkout
Testing & diagnosis · Battery charging circuit
For the Cummins/Onan DL3, from the Cummins/Onan service manual.
Applies to: Cummins/Onan L Series Diesel engine
Before you start
- Voltage regulator VR1 is potted and not repairable.
Procedure
- With engine running, connect a voltmeter across the battery terminals.
- Meter should read 13.5 to 15 volts.
- Charge rate/voltage is determined by battery state-of-charge and circuit resistance.
- Power source is winding CW1 on main stator; if charging voltage is incorrect or missing, check wiring and circuit components.
- Improper operation may be caused by poor terminal connections, broken wires, or a defective battery.
Tools required
- Voltmeter Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Battery charging voltage 13.5 to 15 volts
Source: Cummins/Onan service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.