Hi,

Firstly, I was having the "Check fuses 114 and 115" error - spent loads of time looking at repair guides, online forums, YouTube, manual etc.

Everything came on when switched on, even the test mode was working. However, row 8 and column 8 of lamp matrix did not work. Previously, it also showed check switch 73, 75, 76, 81, 83, clock is broken when entering test mode (There may have been more).

Now, this evening, after all my research, I figured that I would check the switch matrix to try and eliminate some possible problems. I switched on the machine, everything lit up as normal, clock went round and then settled. I went to open the backbox and before I could touch anything, all hell broke loose, the DM showed all different tests, the volume started going higher and higher, it resetted and got louder and louder again - I switched it off straight away. Tried again, with coin door open, nothing worked on any of the four buttons and it went berserk again.

So it came up with "Check fuses F115 and F116, J112 and Opto 12v Supply".

I'm not fully savvy with electronics but I have been spending many hours learning about how to check U20, lamp matrix, switch matrix, soldering techniques, how caps work etc. etc.

All fuses have been checked (out of circuit) and are the correct amps. However, there is one slight question, F115 shows as 3/4A slow blow in manual and other resources, but is shown as fast blow on the pre-printed diagram in the back box?

Can anybody give me a step by step way to start to eliminate the problems? I have ordered a logic probe and I'm considering getting an ESR meter to check caps in circuit.

Many thanks in advance.

Simon

Thanks to LTG and Classe for the responses. I'll give them both a try and see what happens - fingers crossed.

Hi Everyone,

Just a quick update. Having looked really close at the CPU board, it had battery damage, I decided to purchase a new CPU board. The annoying thing is that a few years ago I bought a battery box to use off the board but never got around to fixing it. That £5 spent a few years ago could have saved me £240 today!