LW3 A/B Advice

Judderman

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Mar 28, 2016
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Hi - I had LW3 kicking balls out almost constantly when I was in M/B. In the flasher test, the coils keep firing.

I'm pretty sure that this is the A/B relay not firing, doesn't it? So either relay K1 is bust, or Q29 isn't telling it to fire (or it's further up the chain, but I'll leave further diagnostics out til I've checked these).

I have checked Q29 with my meter & it looks OK, but that was with it still in the board & the board in the machine. Is it possible to test/repair K1, or do I just replace it. Also, in mine, the K1 is the orange rectangle in the pic below, the replacements I have found look nothing like that, is this the right thing https://uk.rs-online.com/web/p/non-latching-relays/8287246/

Sorry for the barrage of questions, but hoping someone can help.

1614024531820.png
 
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strobey

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Tim
Yes i think you're dead right.

Sometimes they stick. Give it a few gentle taps with back of a screwdriver and it might free up.

Long term you'll need to replace it or remove the cap and clean the contacts with some switch cleaner and a slither of thin cardboard.

Don't be tempted to use sandpaper on the contacts, the abrasion will cause poor contact, lead to arching, and worsen the problem v quickly.

Hth. Let us know how you get on..

Tim
 

thejefu

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Feb 13, 2020
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magicwizard
Very same problem I have on my GNR .

I bit the bullet on a PPB replacement board. Selling it anyway so might aswell make her pretty.

Have a relay coming so hopefully will fix the problem on the old board before I replace it. Will put it up here too.
 
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Judderman

Judderman

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Mar 28, 2016
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Tried the tapping fix - sorted it for diagnostic mode, but played a couple of games & it came back periodically - new part due tomorrow, but prob won't get round to fitting it til the weekend.
 
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Judderman

Judderman

Registered
Mar 28, 2016
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Cheshire
Very same problem I have on my GNR .

I bit the bullet on a PPB replacement board. Selling it anyway so might aswell make her pretty.

Have a relay coming so hopefully will fix the problem on the old board before I replace it. Will put it up here too.
*Really* glad you put your pics up - looks like there's a K1 on the CPU board as well as on the PPB - I was looking at the one on the CPU. Deffo saved me from some pain (will even try the tapping solution again.
 

thejefu

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Feb 13, 2020
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Glossop, Derbyshire
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magicwizard
*Really* glad you put your pics up - looks like there's a K1 on the CPU board as well as on the PPB - I was looking at the one on the CPU. Deffo saved me from some pain (will even try the tapping solution again.
Rottendog solved my problem (obviously), but replacing the relay got the old boy working too. Happy days. Good luck with yours.