Diode-testing a TIP122/TIP102 driver on the board
Steps
- With the board out (or the game off), set the meter to diode test.
- Black probe on the transistor's centre leg or metal tab.
- Red probe on each outer leg in turn: each should read about 0.4-0.6 V.
- Any other reading means the transistor is bad; a shorted one usually reads zero or close to it.
Systems
Related tips
- Replace failed TIP122 drivers with TIP102
- Quick test for shorted TIP122/TIP102 drivers
- Replace the pre-driver along with a failed driver
- Solenoid driver transistor positions on the CPU and PPB boards
- How a coil or flasher is switched: PIA to TTL to pre-driver to driver
- 50 V coils use PPB TIP36c transistors, pre-driven from the CPU board
- Three-stage drive for 50 V coils
- Where the TIP122 drivers are on the CPU board
Source: Repairing DataEast 1987 (Laser War) to Sega 1995 (Batman Forever), Part Two, Clay Harrell (pinrepair.com)