For those of you with K-Line experience, I need some tech advise w/ my K-Line K2439-0269 LIRR GP38-2 Diesel Loco. I picked it up online along with an Atlas RS-4/5. Both had running issues. The Atlas was a quick fix and that’s back up and running as it should. I’ll put that up for sale online soon. The K-Line GP38 is not so easy to diagnose. Let me start by mentioning this has K-line electronics, not Lionel or TMCC. I thought about retrofitting it w/ ERR parts but that’ll add $$$ to the repair.
When initially powered up, nothing would happen and the light on the transformer would flash indicating a short. I pulled it apart and noticed a bi-directional diode and capacitor across the + & - on the board which I believe the diode is faulty. On a hunch, I pulled them and retested. The loco now has sound and immediately runs in the forward direction when initially powered up. I believe it should start in neutral, no? If I press the direction button on the transformer, it’ll go into neutral and sound will continue to work. If pressed again (attempting to put it in reverse) the relays click on the driver board and the light flashes on the transformer indicating a short. My theory (without popping the relay covers off) is one of the contacts in the relay is welded closed. I’ve seen this with HVAC control modules before. Does anyone have any ideas or recommendations short of pulling all of the guts out and installing ERR or other? Any help will be greatly appreciated.