The meter shows coil voltage on one lug but nothing on the other.
Voltage on only one lug of a coil
Cause: The coil winding is broken.
Checks
- Look at both lugs; an outer winding end often breaks right at the lug.
Fix
- Replace the coil, or if the break is on the outer winding, peel back the label, unwind one turn, sand off the enamel and resolder it to the lug.
Systems
Related tips
- What the coil diode does and how a bad one shows up
- Which coil lug takes which wire
- A coil has power but never fires
- Firing a coil by grounding its ground lug
- A solenoid does not fire in the diagnostic coil test
- Fit a coil diode with its band on the power lug
- Low coil voltage from pitted L/R relay contacts
- Testing a coil diode
Source: Repairing DataEast 1987 (Laser War) to Sega 1995 (Batman Forever), Part Two, Clay Harrell (pinrepair.com)