LGB phase iv coach lighting problem

[Darren Lalonde]

I have an amtrak lgb amtrak phase v coach. not sure of model number. it has 21004 on it.

I am using an MTS system so A/C and the lighting on the coach seems to short circuit the track.

I have tested the bulbs independently and all works fine. I suspect the board with the switch on but don't really know what could be wrong

Any ideas?

 

[ntpntpntp]

item 32220 according to google.

Can you try the coach on analogue - see if it trips a DC controller?

 

[Darren Lalonde]

i've tried connecting dc 12v power to the pick ups as dont have dc controller and still shorts

 

[ntpntpntp]

hmm... needs a bit of investigating then. I don't know this model nor how it's wired.

 

[PhilP]

My guess would be a trapped wire, either on the bogie, or under s screw / weight (if any) in the coach..

 

[Darren Lalonde]

I have taken the coach apart. I'll send a photo when i get a minute. There is a switch unit with a circuit board with what i presume is a transformer...

I also have another coach so will try and compare.

 

[Darren Lalonde]

This is the board from the coach.


The two sets of un soldered connections near the two 'red' go to the wheels.

 

[Neil Robinson]

This is the board from the coach.
The two sets of unsoldered connections near the two 'red' go to the wheels.

I presume one pair of wires go to each bogie. I wonder if these have been crossed during manufacture.
I suggest you connect only one pair to the supply voltage with the lights connected. Apply about 18V to 20V ac or dc to the wheel wires. If all is well using DC swap the wires over to check with the other polarity simulating analogue running in the other direction

 

[James Day]

I presume one pair of wires go to each bogie. I wonder if these have been crossed during manufacture.
I suggest you connect only one pair to the supply voltage with the lights connected. Apply about 18V to 20V ac or dc to the wheel wires. If all is well using DC swap the wires over to check with the other polarity simulating analogue running in the other direction

Looking at the image of the rear, the top unsoldered connection looks rather 'nasty'. I would be tempted to rake around that (especially at the top) and the other unsoldered bits too, whilst you are at it, just to make sure it has not been clumsily unsoldered and something there is shorting.

If something had failed you would hope to see some evidence of it wouldn't you? A reassuring scorch mark or something!

Does the coach have 5v lighting or something similar?

James

 

[Darren Lalonde]

Thanks to all who replied. I sent my board away in the end for repair to a local electronics expert. Apparently the diodes had failed. All works fine now

 

[PhilP]

Glad you have it sorted, and nice to get feedback on the actual problem.
PhilP.