TECH: DE JP T-Rex no left/right

Grbgemen

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Yet another JP. :) Left/Right motor not working during start up tests or during gameplay. Can only hear the relay click. Up/Down motor works just fine. Eats the ball just fine. Oh and game is running 5.01 software too.

So far:

- Motor tests good with a 9v battery applied.
- Reflowed relay board that controls Left/Right motor
- Replaced Q24 and its predriver (Drives Left/Right motor)
- Replaced Q27 and its predriver (Drives Bi-Directional Relay controlling voltage polarity for Left/Right motor)

Reading over the theory of operation service bulletin, says to check fuse F1 on the shaker board. 99% sure I checked it already but will check one more time when I get home. Other than that, I dont have a clue. :confused:
 
I have not had this particular issue with my JP, but the recommendation seems to be - remove the L/R relay board from under the playfield and re-flow all of the solder joints and try again.

RussMyers
 
Have you tested the motor in the diagnostics menu? If so, does it work at all? I imagine it doesn't.

The manual states that it is a 5v DC motor. I'm not sure what voltage is applied to it in the game, but have you tried it with a lower voltage? It could be that the motor is bad and 9v is enough to get it going outside the game, but the game itself doesn't supply enough voltage to make it work.
 
Got it! Cold solder joints on the backside of the motor control board. Left and right is now working. However I do think the motor is on its last leg as it is pretty sluggish. Anyways, thanks for the help guys.
 
Good deal. Mine is rather sluggish on startup but it seems like as the game is on it moves quicker.
 
Make sure you have the latest roms for the CPU. It will pulse the motor so it does not wear out as fast.
 
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