Hi guys, I have a older sync 250, 1998 model, Serial kj245050. The issue i'm having is this.

When i step on the foot pedal, the gas valve relay opens and I receive gas, but the HF and output don't activate. The 3 relays that control all the functions are receiving proper voltages. When i flip the output switch from remote to panel I still don't receive any output. However, the gas relay activates again.

My main question is, the HF relay and output relay are they controled by the main PC board that sits behind the bank of relays? As in, when i depress the foot pedal the gas relay activates because it is directly wired to the pedal from what I understand, but is the PC board what tells the HF and output to turn on? I've gone through all the wiring in the machine and its top notch, no lose or corroded connections. The HF points are in good shape, everything is hooked up properly. This just suddenly happened, i was chugging along welding, finished up my bead, and when i stepped on the pedal again i got nothing!. After fiddling around with connections inside the machine on the main PC board it started working again for a short while and then it just stopped again. Anybody have any suggestions as to what the issue may be? Is it possible that the PC board has gone bad over time?