Jurassic Park sling, bumper, missile issue

Lefttee

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Not sure where to start. Still new to fixing these things. Anyway, I have a JP that when I launch a ball and it goes throught the T-gate and hits the left bumper it fires the smart missile and fires both slingshots. Any info or point in the right direction would be great.
 
Welcome to the fun of pinball ownership. When they work right they are a lot of fun, when they do not wook they can be downruight maddening.

First off, has this game always done this or did it just start behaving this way? What has been done to this machine lately?

Second, I need to direct you to the great pinball repair guides that are at:

http://www.pinrepair.com/

There is a link to ones that are for Data East, I suggest that you read the whole thing, and there is a special section:

http://www.pinrepair.com/de/index3.htm#switch

on the switch matrix, which seems to be what you are having an issue with.

Finally, you need a manual for the game, It will include schematics, assemble drawings and part numbers. An electronic copy can be found at ipdb.org.

If you look in the manual on page 26, there is a chart listing where the switches are located in the matrix. The issue that you are seeing is related to column 6 since the switches that you mentioned are in that row. It sounds like the CPU thinks that all of the switches in that row are closed when the pop-bumper switch is closed. Read up on the procedures in the above link, and then look for any obvious issues, broken wires, shorted contacts, if you worked on the game, or stuck your arm into the coin-door, the diodes on the trough can get shorted to the metal trough and cause these weird actions also.

Let us know what happens.

Goose
 
I picked this game up in December, moved it into my basement and haven't done much with it since. When I bought it I don't remember it having this problem, so possibly the move has caused this.

I will read over the guide at pinrepair and see what I can find. Thanks
 
As already mentioned, go to the links provided amazingly helpful for new pin owners as well as those of us that have owned for awhile.
Yes from what you have described it is likely an issue involving the switch matrix.
If you have a manual it will have a matrix layout, If you dont have a manual, get one.

Due to the matrix, what can happen is that one switch shorting can cause other switches on the same line of the matrix to react to the problem. One of the issues with this is that it can mask which switch is the real problem. Since you have a few switches reacting, they should line up on the matrix, and then you should check all the switches in line with the switches causing problems.

It maybe possible that while moving a wire or a diode came loose from a switch. It is common for wires to break from switches and coils because that little metal ball makes for alot of hard knocks.

Good luck and enjoy your JP, its a good game to own.
 
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