Cummins/Onan GTA14 / GTA14 qi 20 NA — Ignition Coil Check
Testing & diagnosis
For the Cummins/Onan GTA14 / GTA14 qi 20 NA, from the Cummins/Onan owner's manual.
Applies to: Cummins/Onan GTA14 qi 20 NA, Cummins/Onan GTA14 engine
Procedure
- Turn engine off and disconnect batteries.
- Visually check coil for cracks, carbon tracking and physical damage.
- Disconnect wiring to the coil.
- Connect ohmmeter to positive and negative terminals and read primary resistance.
- Connect ohmmeter to coil positive terminal and high-tension terminal and read secondary resistance.
- Reconnect all wiring and batteries.
Tools required
- Ohmmeter Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Primary resistance should be .2 to .3 ohms
- Secondary resistance should be between 6K ohms and 11K ohms
- Infinite reading indicates open winding; replace coil
Full service-parts list: Cummins/Onan GTA14 qi 20 NA →
Source: Cummins/Onan owner's 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.