KevJB
Well-known member
My board shows K1 and K3 relays differently than marked in your attachment above. Your K1 & K3 should be swapped. Boards are same rev. See below:Ok so it sounds like it is turning on but then there might be a short between the SWG power leads. That could be due to the other relays (K2 & K3). K1 connects the AC power to the rectifiers and K2 and K3 swap the plus and minus leads to change polarity. If one of the relays changes but the other doesn't, then there is a short although, I would have thought that the fuse would blow under that condition so I am not entire sure that is the cause. Another possibility is the sensor that measures voltage between the +- from the rectifiers. The problem is these boards are not all that easy to fix or troubleshoot. The only thing that is easy to fix is a bad solder joint on K1 which is the usual culprit of these types of problems. K1 has three leads that you can see if you turn over the board. If there is a problem there the solder joint might look burn and/or dull. You did check fuse U correct?
View attachment 359919

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