Cummins/Onan — Battery Cable Checkout
Maintenance · Battery cables
From a Cummins/Onan service manual covering: MDL3, MDL4, MDL6. Check it applies to your exact model before use.
Applies to: Cummins/Onan MDL3, Cummins/Onan MDL4, Cummins/Onan MDL6
Procedure
- With the starter motor operating, check the voltage drop from the battery negative post (not the cable clamp) to the cylinder block.
- Check the voltage drop from the battery positive post to the battery terminal stud on the solenoid.
- Each voltage drop should normally be less than 0.3 volt.
- Thoroughly clean all connections in any part of the circuit showing excessive voltage drop.
Tools required
- Voltmeter Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Each voltage drop should be less than 0.3 volt
Full service-parts list: Cummins/Onan MDL3 →, Cummins/Onan MDL4 →, Cummins/Onan MDL6 →
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.