Cummins/Onan 3.6MKY / 4MKY — Starter Voltage Check
Testing & diagnosis · Electric starter
For the Cummins/Onan 3.6MKY / 4MKY, from the Cummins/Onan service manual.
Applies to: Cummins/Onan 3.6MKY, Cummins/Onan 4MKY
Procedure
- Connect a voltmeter between the start relay output terminal (starter motor lead side) and ground.
- Press the start switch.
- If approximately 12 VDC is present but the starter does not crank, the starter is defective.
- If no voltage, check the battery, start solenoid and control wiring.
Tools required
- Voltmeter Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- approximately 12 VDC
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.