Checking lamp signals during test step 16
Steps
- Enter self-test step 16, which steps each lamp data line from low to high.
- On the control board, probe LD1 at Z32 pin 4; the twelve strobes DS1-DS12 appear on even pins of Z34 and Z35.
- When LD1 is high at the moment DS1 pulses, latch 1 on the driver board stores it and its lamp should come on.
- If the strobes and data are present but a lamp group stays dark, move to the driver board latch and transistor.
Systems
Related tips
- How driver board lamp latches work
- Driver board A3-J3 lamp groups and relays
- None of the controlled playfield lamps work
- One or more controlled lamps never light or stay on
- Driver board A3-J2 backbox lamps
- Where coil, sound and lamp commands come from
- Switch test (step 18) shows switches closed
- A driver board output is stuck on or dead
Source: System 80 Service Manual, Gottlieb