Demolition Man Cryo Claw Intermittant Problem

[Hashman]

Well, I picked up my new demo man the other day and im really happy with it except the cryo claw has decided to stop moving over to the right to get the ball offthe elevator intermittantly. The claw nudges right slightly and then stops completely. When the ball hunt kicks in on the 2nd run it usually moves the claw over and picks up the ball and then brings it all the way back left and drops the ball.

When turning on the machine the claw does its normal right/left swing no worries. When it IS working and i go into the test menu everything checks out ok. Doing the claw right test moves it all the way to the right and then the X comes into the little box just like it does testing claw left.

When it fails and i enter the test menu, the claw left/right test only nudges slightly each way and then immediately the X shows in the box (optos switch closing?). So If i continue to press the test button it will finally move all the way over. (sorry if im sounding muddled).


I have checked and cleaned the elevator optos and they seem ok. Ive searched on the net high and low and checked the driver board for any burnt plugs (as someone had this poroblem when they had a the GI connecter connected. I actually toook of the GI connected and the claw worked for about 6 times and then failed again so i don think  that is the cause.

If the opto's in the claw (pain to get to because all the ramps have to come off) have failed or are dirty would this give this problem? And would it be this intermittent? The motor obviously works so im finding im getting very frustrated,. Any ideas?

Thanks Dave

[dj10555]

Hi Dave,

The optos on WPC games can go intermittent. Another way to test the optos is to run the 1st switch test in diags. Leave it on this screen for 1/2 hour or so and see if any optos/switches trigger by themselves. You can also block each opto with a piece of paper and see if it responds correctly.

The GI connectors do burn on these games after a lot of use but this will normally cause GI lighting problems and shouldn't cause a problem with optos.

regards Derek

[Hashman]

thanks dj. I will try the switch test tonight. the claw optos are a hssle to get to as every single ramp has to come off to get to them. also they are definately closing before the claw gets to its end position when it does fail. ive also read that some people had re-seated the roms as when the claw fails the claw countdown stays at 9 and doesnt countdown! so i might reseat all of those tonight as well as the seller swapped the original roms with the swear roms. hopefully one is quite seated properly.

[Hashman]

FIXED!

Rather than get a tech to charge me 100's of dollars, I decided to pull apart my demo man and try and fix myself. Rather than removing every single ramp like id read on the net, I managed to remove the plastic ramp holder around the claw with some wrangling. Disconnected the motor and magnet wires from under the playfield. Undid the claw bolts from the back and mananged to lever it up to an angle where i could get the cover off. Unplugged the opto board cable and managed to get the entire claw mech out! :)

Took off the opto board and ran a cotton bud with windex through the tiny horseshow optos. Somehow managed to re-assemble everything without breaking anything and fired up the game. CRYO CLAW NOW WORKS PERFECTLY EVERYTIME!

To say im proud of myself is an understatement. I was really stressing id break something but took care and have now probably saved myself of over $300 for a tech to do it. Plus demo man really kicks some ass with the claw working everytime! So happy! 

[goodolddays]

Excellent result . Well done