Finding a short

[Spandangler]

hey peeps

Yesterday whilst playing wh20 the bottom half of the GI went. I think it was F108 blown. I'd noticed it was flaking out before it went, lights were flickering when flippers were pressed (assuming it was the vibration). I checked under the hood and could see nothing obvious, so is stuck a 5a circuit breaker in and it was fine. So I put a new fuse and played several games.

Turned it on again tonight played several games then noticed the lamps flickering, then going out and coming back on again then fuse blew again.

Lifted the hood, had a good look but still can't see a short. I'm assuming it's something just touching somewhere which is just enough to go when the flippers vibrate but can't see anything for the life of me.

I can click the circuit breaker afterwards and the lamps come back on so its not short the entire time.

For now I'm just leaving the circuit breaker in as its so random.

So I guess my questions are, is it possible to check for a short using a meter or could it be anything board component related?

These little faults drive me nuts

Thanks guys

 

[pinballmania]

Break the gi circuit down into sections by desolering the linking wires. Reintroduce each section until the fault emerges. Then break that section down into smaller sections. Repeat until you've honed into the fault.

 

[Spandangler]

Thanks Andy. Makes sense. It's just that its so random at the moment it could take weeks at that rate. I assume it's that black and white with gi. It's either working and if it's not and blowing a fuse, it's a short?

 

[pinballmania]

If it's random then go around each lamp in the string. Examine each one for potential shorts. Prod each one with your finger to see if you can induce a short. You'll see the light dim if there's an issue.