Cummins/Onan 6.5NH - 3CR / 6000 A — Battery Ignition Coil Test
Testing & diagnosis
For the Cummins/Onan 6.5NH - 3CR / 6000 A, from the Cummins/Onan service manual.
Applies to: Cummins/Onan NH engine
Procedure
- Use a Simpson 260 VOM or equivalent.
- Place the black lead on the ground (-) terminal of the coil and the red lead to the positive (+) terminal; primary resistance should read 4.30 (+/-10%) ohms at 70 F.
- Change the resistance setting and place the ohmmeter leads inside the spark plug cable holes; secondary resistance should read 14,000 (+/-10%) ohms at 70 F.
- If any condition is not met, replace the ignition coil.
Tools required
- Simpson 260 VOM or equivalent Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Primary 4.30 ohms +/-10% at 70 F
- Secondary 14,000 ohms +/-10% at 70 F
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.