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Jurassic Park Monster head problem.

BallyWilliams suck

BallyWilliams suck

Registered
10 Years
Joined
Jul 21, 2011
Messages
457
Hello, I thought I'd post this as I've had a quick look at the problem, and can't seem to solve it. Mainly because I don't have a manual (and less mainly because my tinkering didn't seem to sort it!).



Monster head moves up and down and bites the ball fine - but it doesn't move left or right!



The underplayfield relay operates, but the motor doesn't move left or right. I've traced all the wires back, and they all have continuity (and I replaced the relay with a spare), so I assume bad wiring isn't the issue. The red powerline has power, and the transistors on the CPU seem to be switching ok when L/R flipper button is operated to supposedly move head L/R.



From what I could make out from the IPDB manual, one wire goes off from the relay board to the cabinet shaker board and motor, but this shaker board is missing from the game. I seem to be missing a ground (I think) and was wondering if perhaps the ground comes from or through this this board? [attachment=16:0.jpg]



If anyone has a spare 5 minutes to have a quick look - or better still, disconnect this board in their JP and see if the head stops moving L/R!



Cheers!



J
 
Not really - I haven't actually worked out WHY it needs to move left or right.....It's just winding me up!
 
i believe the reason it moves left and right is purely to mimmick following the ball, you can disable this function in the menu.
 
this is what it says in the pinrepair document thingy:



Problem: The dinosaur on my Jurassic Park is not working correctly. He won't turn

right or left, and his mouth won't pick up the ball. What is wrong?



Answer: There is a small under the playfield relay board that switches the

movement of the dinosaur from right to left. Often the header pin solder joints for

the relay board's connectors are cracked. Resolder the header pins. Do that first

before any other repairs. If problems still exist, there is a cable that runs through

the inside of the dinosaur. From the constant movement of the mechanism, often the

wires inside this cable break. This can make the dinosaur work intermittently, or not

at all. This is the usually the problem when the dinosaur's mouth will not open or

close. Also there are a set of switches to sense when the dinosaur is right, left or

center. Use the games internal switch test to make sure these switches are working

when the dinosaur moves to these positions.



smile-1.png
 
Hi Dan - I've looked into it a fair bit already, and managed to sort the basic bits (including the always broken wire to the mouth movement).

I've tested the left / right movement switches, which activate fine, showing the head is in the fully left or fully right position. The relay seemed to function properly, but I swapped it for another just to make sure. It also seems to have power, and is getting it's feeds from the CPU transistors ok when operated.



I don't have a manual, but one wire seems to go off to the shaker motor board (which is missing), so I'm wondering if it's missing a ground or something from this board not being connected.



I was hoping someone with a JP would try disconnecting this board and see what happens for me
wink-1.png
 
Can't believe it will depend on the shaker board being there. Can we assume that it is not currently disabled in software setup?
 
Hi Andy - I was hoping you'd pop along at some point !



It's enabled in the menu, and when the game boots, the relay clicks as if it's trying to move the head left and right (during startup diagnostics).

I've tested the motor by applying power directly and it works. I suppose I should look for a decent manual - but the phocopied page doesn't make a lot of sence to me, as the relay seems to send power all over the place.......



It seemed to half work when I took a ground from the opposite relay board, so I think it's a ground that it's missing, although I had to move onto a R&B rebuild and have shelved the JP.....For now.....
 
Well, having now actually looked at the manual, i can confirm that the left right direction connection is routed via the shaker motor fuse board. It appear to be just the fuse and a diode mounted here. So a little extra wiring should bypass the need for this board. The relay board acts to reverse the direction of the motor.
 
Oooooh, thanks Andy! Without being cheeky, did you happen to notice which wires would need bridging, and if these wires would need a diode inserting? I've not got the machine infront of me now, and the manual I have isn't very clear
sad-1.png




Thanks! ! ! !
 
Looks like J1 pin 4 via Fuse and Diode to J3 1 and 3.



[attachment=27:jp motor.png]
 
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