Even though you have replaced it, I’m inclined to steer you back to the RCM as suggested above. I’m a radio tech with lots of experience with defective solder joints. The culprits are usually the high current solder connections to the printed board. You need a jewellers loop to actually see that the thicker pins have separated from the solder. When resoldering concentrate on heating the larger relay pins, not the solder trace and let the solder flow from the pin and onto the trace. Assuming you have desoldered and cleaned with flux remover. it solved all of my no start problems. I believe there is a lot more info on RCM fixes on the forum.