Re-measure the coil after replacing a shorted driver
A coil that was held on by a shorted transistor may have cooked its insulation. After changing the transistor, check the coil on ohms; a reading well under 3 ohms means the coil will take out the new transistor and must be replaced.
Systems
Related tips
- Measure every coil before powering up new driver transistors
- Always check the coil diode when a driver transistor has failed
- Finding a coil's driver transistor without a manual
- Constant power coil drivers Q8-Q13 and Q23-Q30
- Use the manual's coil/flasher chart to find driver transistors
- A low resistance coil means checking its driver chain too
- Checking for voltage at a coil
- A broken diode on a non-flipper coil often kills its driver
Source: Repairing DataEast 1987 (Laser War) to Sega 1995 (Batman Forever), Part Two, Clay Harrell (pinrepair.com)