Anyone have schematics for the 500 series?

[modessitt]

I'm specifically looking for the section for the switch inputs from the connector on thru. I need to repair some corroded traces that were under the green battery and are now causing door open errors (M, MB, B). I shouldn't have to buy another board for something like this, but I don't want to unpopulate the board just so I can find a trace's end points.

Thanks.

[Jim]

I just recently sat down and figured this out, I had 15 boards with the same problem.  got 12 of them working.  I have 3 pdf's and 4 pictures that will show all the information you are looking for, but I don't know how to transfer the data into the forum. basically there are 8 tests to preform on the traces, from component to component,  there are four of the eight that are usually open,  the traces on the board are not of any substance to be soldered too. they damage very easy. I ended up soldering directly to the IC leg point to point. If you have large build up of corrosion around some of the IC's, green and blue crud between the legs and underneath the IC, usually causes those devices to come loose from their respective pads and cause other problems other than the traces being open from the battery corrosion.  the board itself has a heavy coating of green substance to protect the eyelets and traces during the soldering process. this has to be scraped very carefully to expose the copper so you could measure the continuity of the trace. I used a meter that has a open/ short function that generates a tone when a short  (continuity) is detected.  start to finish, it took me on average 1 hour and 45 minutes per board to fix. debunked the MYTH that soldering the two positives together would solve this problem. IT DOESN'T,  just by dumb luck the one trace that runs close to the battery hole is one that opens right there, glob soldering usually gaps the opening and repairs that trace. it doesn't  happen all the time. I use the battery holes to run wires through to the other side of the board.

Jim

[Amechanic]

Jim,  I'd be interested in seeing what you did to repair those boards.. I my self have a hand full of DOA MPU boards...

Gary

[modessitt]

Sent you a PM, Jim.

[Fredoetisa]

Hi,


Is it possible to have the schematic of the 500 série mpu board ? I have a 502 rev a mpu 5 reels and search everywhere the schematic...


Thank’s