Quoted from GRUMPY:
Yes. There are videos on U-tube on this. As for your flashers not working, start by using a jumper wire hooked to ground and briefly touch the other end to the metal tab of correct transistor. If the flashers light with the jumper, then you have a board issue. If the flashers don't light with the jumper then you have a bad dropping resistor or burnt out bulb.
Success! I changed out Q32 and 18, all good now. The backbox flashers are working now with new bulbs and cleaning the sockets. For a while only the left 2 lamps were lighting, then none. I was thinking these were paired like the PF flashers but I see all for are driven by one transistor. I think you said earlier that these are wired in series so if one bulb is out the other won't light? When ohming the warming resistors, I was getting 168 ohms on the 330 ohm resistors, but I think it was picking up the entire circuit or the two 330 ohms were paralleled since there are 2 warming circuits in the back box? It's been almost 40 years since I took electronics in school but I remember some of ohm's law. To get the total resistance from a circuit of paralleled resistors, you take the reciprocal of each resistor value then add them together? Heck IDK!
Another goofy thing I did tonight, I have an extra sys 11 CPU that I bought maybe 8-10 years ago and has been sitting since. Was supposedly good when purchased, no corrosion at all. I wanted to try it before fixing the other CPU. I had 2 locked coils, both specials and almost smoked the left pop and left sling. That would be Q69 and 75.
After fixing original CPU and putting it back in and plugging in connectors, I noticed 1J18 is keyed at pin 1. This was stupid because I may have been off by a pin previously on the spare CPU causing those coils to lock on. What puzzled me was that the coil fuse was not in the board, yet the coils came on. Now I see what all the fuss is about special solenoids.