Dear All,
I recently bought an Mth 20-2242-1 DC-3 Inspection car in the UP paint. I purchased it brand new with a 5v board still in it. I did test run it with the white battery, and I went to do something else. When I returned and fired up the engine, I got a dead short. I do not think it is a "board blow up" problem because there was no "white smoke" or burning smell, and I get the relay click and lights right before the short. I will replace the battery with a green one. Any suggestions?
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its a shame how many people power up a ps2 5 volt bard with a 8.4 volt white battery after so many people had told many many many people on this forum NEVER POWER UP A PS 2 8.4 VOLT BOARD WITH A WHITE BATTERY YOUR ONLY going to BLOW THE BOARDS, I WISH PEOLPE WOULD LISTEN I NEVER POWER UP A BOARD OF A USED TRAIN UNTIL I CHECK THE BATTERY AND LOOK THE ENGINE OVER FIRST.
now it will cost you a new ps 2 3 volt board to repair the engine at a minimum! your board is now trash and can't be repaired!
Alan
I'm afraid that Alan may be right, a direct short is a very common 5V PS/2 board failure mode.
I can repair it for you if needed, send me an email and we can talk bout your engine!
Alan
Before panicking, I would unplug the board and see if perchance the short is elsewhere,
I'm not holding out hope, but if you pull the 7-pin connector off the PS/2 board, you can see if the short still exists. That's the only place track power goes to the PS/2 board stack.
After many tests, I can hear the relay click, and see lights come on about 1.5 seconds before the short. Video attached. You can clearly hear the relay click and lights come on.
John, where is the seven pin connector on the 5v board? Thanks for your help.
The 7-pin connector is on one of the long sides, it's all alone. Pulling that will totally disconnect the board from track power.
If you change the track voltage do the lights come on at the same brightness during the albeit brief 1-2 seconds before it shuts down? And does that 1-2 sec shutdown time get longer or short as a function of track voltage?
The relay click is of course a good sign since that means the processor has started running its program. If the lights then come on at constant-brightness (in other words, independent of track voltage) that's an even better sign since the processor runs a complex algorithm to convert variable AC track voltage to constant brightness control of the incandescent bulbs.
Do you have any method of measuring the AC current (like a Z-4000 Amps readout) flowing to the engine? I'm curious if it draws a lot of current when it shuts down. I'm trying to imagine a scenario where some kind of short on the output side (lights, audio, motor) is over-loading the board's DC low-voltage supply which shuts down the engine.
Any pinched wires, especially purple or motor leads? As Stan said, click is good. I would remove the 12 pin, 4 pin, 8 pin and leave 2 pin battery, 7 pin power and 5 pin motor connected. Does it power up, and click with out short? It will be silent and no lights, but if no short, press direction button. If it runs, you have a short in the wiring, or could be a defective board on one of the lighting or sound issues. Add back 4 pin smoke, 8 pin markers, and finally 12 pin one at a time to help isolate the issue.
If still shorts will everything removed but 7 pin, and short clears when 7 pin removed, the board is in fact shorted. If shorts with 7 pin not connected, the wiring from trucks picking up AC power are shorted. Check the red and black wire. G
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