Cummins/Onan — Testing Field Windings for Grounds
Testing & diagnosis
From a Cummins/Onan service manual — check it applies to your exact model before use.
Applies to: Cummins/Onan MCCK
Procedure
- Disconnect all field leads before testing.
- Touch one test prod to F1 (+) and the other prod to the frame.
- The buzzer should not sound or the lamp should not light.
- If the tester buzzes or lights, the field is grounded and must be replaced.
- Test lead F2 (-) in the same manner.
Tools required
- Continuity tester Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Full service-parts list: Cummins/Onan MCCK →
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.