Hello,

Helping a newbie. Game is getaway. Issue is verified in the PDboard.Trough coil was burnt. Replaced q54 and all components associated with it as they were toast. Even the U4 Driver chip 74ls374. Problem is the coil still pulls in on power up. When 5 vdc removed from the driver bd, the coil will not lock on which leads me to believe another ic is bad on the board possibly.. I still have something backstream on this driver bd that is causing the issue. Any help would be appreciated. The rest of the circuits lamps etc work fine. Its this only driver circuit q54 with issues. This is an odd issue as its not cut and dry as usual. I have 20+years with these wpc's and can fix almost anything and this is a stumper

Thanks in advance! JR

Thanks for the help.the link will help. I will try and clean up more and see if that helps.

Thanks for the help. Cleaning ip all oxidation and burn area solved the issue. I must have had continuity on the burnt area.