Balrog issues have been documented a lot, but this one's got me stumped. The Balrog on my LOTR is trying to move when it shouldn't and the usual fixes are not helping.
At the start of the game, the Balrog correctly moves to unblock the centre ramp. As soon as the ball is plunged and again throughout the game, it repeatedly attempts to continue this rotation. The invalid Balrog movements are triggered when certain switches are hit, but not always all of the same switches. With the Balrog removed, a false trigger will cause the Balrog motor post to rotate one full circle and stop again where it should.
During troubleshooting I've found the Balrog is inappropriately triggered every time by some switches (shooter lane, lower right orbit, POTD, left inner loop gate switch etc.), never triggered by others... and only occasionally by the left outlane, left inlane and Spot Ring switch.
I've also 100% confirmed (glass off) Balrog is triggered once by each individual callout during Gollum MB while no other switches are tripped!!
The attempted movement is always in the direction the motor was last told to rotate. Counterclockwise to start the game, but if I start FOTR MB, Balrog correctly moves to block the ramp, then all false triggers move Balrog in the clockwise direction. With Balrog removed each trigger results in a single 360 degree rotation. With Balrog mounted, it pulses a few times as it tries to push its way past the post/ramp blocking its way.
In test mode the Balrog works perfectly.
Over a period of weeks I've tried a number of the usual fixes, in this order, with no success.
1. Reflowed all solder on the Balrog motor relay board, replaced board diode
2. Replaced only Q22 (BALROG MOTOR) with new TIP 102 (even though it seemed to test ok). Tightened board to ensure good ground.
3. Replaced both roller switches and diodes on the Balrog drum unit with new
4. Replaced Balrog motor relay with new one from Mouser, new header pins on relay board
5. New relay board connector using trifurcon pins
6. New connectors and trifurcon pins on either side of the z-connector at the Balrog motor.
7. Swapped I/O driver board with working one from my TSPP.
8. Put original driver board back, swapped in TSPP ribbon cable at J1
8. Replaced connector J7 (lower current solenoid) using trifurcons
9. Reseated CPU chip (v 10.0)
Batteries are good, no leakage. Game is HUO, no hacks. POTD LED figurine lighting, BG eye flasher and stronger flipper coils are the only mods.
At this point I am studying the schematics and suspect a chip/logic issue (I don't have a logic probe). I think I've covered all the under PF possible causes and since my TSPP I/O driver board swap did nothing, I'm not sure where else to look but upstream.
Could a flakey opto be at fault?
Perhaps something related to the DMD? (Gollum MB callouts are each accompanied by a new graphic.)
Any suggestions you might have would be appreciated.
Thanks,
At the start of the game, the Balrog correctly moves to unblock the centre ramp. As soon as the ball is plunged and again throughout the game, it repeatedly attempts to continue this rotation. The invalid Balrog movements are triggered when certain switches are hit, but not always all of the same switches. With the Balrog removed, a false trigger will cause the Balrog motor post to rotate one full circle and stop again where it should.
During troubleshooting I've found the Balrog is inappropriately triggered every time by some switches (shooter lane, lower right orbit, POTD, left inner loop gate switch etc.), never triggered by others... and only occasionally by the left outlane, left inlane and Spot Ring switch.
I've also 100% confirmed (glass off) Balrog is triggered once by each individual callout during Gollum MB while no other switches are tripped!!
The attempted movement is always in the direction the motor was last told to rotate. Counterclockwise to start the game, but if I start FOTR MB, Balrog correctly moves to block the ramp, then all false triggers move Balrog in the clockwise direction. With Balrog removed each trigger results in a single 360 degree rotation. With Balrog mounted, it pulses a few times as it tries to push its way past the post/ramp blocking its way.
In test mode the Balrog works perfectly.
Over a period of weeks I've tried a number of the usual fixes, in this order, with no success.
1. Reflowed all solder on the Balrog motor relay board, replaced board diode
2. Replaced only Q22 (BALROG MOTOR) with new TIP 102 (even though it seemed to test ok). Tightened board to ensure good ground.
3. Replaced both roller switches and diodes on the Balrog drum unit with new
4. Replaced Balrog motor relay with new one from Mouser, new header pins on relay board
5. New relay board connector using trifurcon pins
6. New connectors and trifurcon pins on either side of the z-connector at the Balrog motor.
7. Swapped I/O driver board with working one from my TSPP.
8. Put original driver board back, swapped in TSPP ribbon cable at J1
8. Replaced connector J7 (lower current solenoid) using trifurcons
9. Reseated CPU chip (v 10.0)
Batteries are good, no leakage. Game is HUO, no hacks. POTD LED figurine lighting, BG eye flasher and stronger flipper coils are the only mods.
At this point I am studying the schematics and suspect a chip/logic issue (I don't have a logic probe). I think I've covered all the under PF possible causes and since my TSPP I/O driver board swap did nothing, I'm not sure where else to look but upstream.
Could a flakey opto be at fault?
Perhaps something related to the DMD? (Gollum MB callouts are each accompanied by a new graphic.)
Any suggestions you might have would be appreciated.
Thanks,
