DC/DCC puzzle

dutchelm

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A simple job, fit a decoder in to a LGB 22355 maintenance tram. Direct decoder so just plug one in.
First problem was getting the 8 pins into the very tight sockets, extreme force required, even after sockets had been opened up a bit.
Then program the decoder, a few problems here as the MD decoder was different to a Massooth decoder but sorted.
Then the test run. The tram ran fine on DCC but went backwards on DC. Normally I can swap the track wires on the decoder but it is plugged into the main board & fixed . If I reverse the motor it will fix the DC but then the DCC will be reversed, likewise if I change bit 0 on cv29. If I swap the pickup wires on the motor block it means the track doesn't line up with the trailer plugs on the cabs.
Am I missing something?
 
very common:

hook up system
test direction on dcc.... if loco runs backwards, swap wires on motor, or set reverse bit in CV29
now test on DC, if it runs backwards swap TRACK PICKUPS (not motor)

but you have several situations that don't let you swap the track pickups? cut wires and swap..

I am a firm believer is not using the reversing bit in CV29, have found too many decoders that had issues later..

Greg
 
Is the front light and motor backwards (I am assuming CV 29 is set to an even number)? If so, reverse the outer wires on the 4 wire cable connecting to the top of the motor block.
 
If I swap the pickups, the front & back trailer plugs are the wrong polarity. This was supposed to be a DCC ready job, plug in & go.
I have now sorted it by swapping the decoder for an old LGB decoder. It all now works.
 
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