Chipping An Lgb/aster Ngg13 Garratt

L1070031.JPG L1070031.JPG Attached is a photo of my Garratt with the 2 x 55021 decoders fitted and the 55026 cable connected to one of the 55021s. I'm trying to programme it using a 55045 but initially when trying to 'Read out Main data' I got a message saying 'Maximum input current exceeded'. I am using a 1amp 50083 to power the 55045. After a couple of goes I got 'EPROM not readable'. I tried switching the main switch to sound and no movement but still the decoders are not being detected. Any ideas?

L1070031.JPG L1070031.JPG
 
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Turn sound OFF.. Turn lights OFF.. - They will pull current as the loco tries to come to life whilst programming.

I think you may have to program the decoders individually for a start.. Try pulling one of them, so it is not powered.

Worst case is you have to program the decoder outside of the loco.
 
Phil, thanks for the swift reply. I tried it with one decoder fitted and with the switch in position 0 but still get the same 'Maximum input current exceeded - Are other parts than decoder connected'. I then get the EPROM message too. The loco is on a programme track, with nothing else. I've successfully programmed two other locos tonight. It's getting late here so am off to angst about it in bed.
 
Phil, thanks for the swift reply. I tried it with one decoder fitted and with the switch in position 0 but still get the same 'Maximum input current exceeded - Are other parts than decoder connected'. I then get the EPROM message too. The loco is on a programme track, with nothing else. I've successfully programmed two other locos tonight. It's getting late here so am off to angst about it in bed.

I think you will find all the analogue part is still being powered, and that it is too much for your system..
It should be fairly easy to hook up the decoders individually. - Just a pain to do, but how else would you be able to set just one to drive lights etc?
 
Morning update.

When I press the Read out Main data' button (with the loco switch in any of the 4 positions) I get an initial message of 'EPROM not readable' but then it does start to read CVs and gives me the read out. The message 'Decoder type e.g LGBE_V2/V3: ATTENTION, some other areas/limits for ' is shown. Unlike the other locos, there is no movement along the programming track.

I then swapped the cables of the 55026 from one 55021 to the other 55021 and am back to square one, with the message Max current input exceeded and EPROM not readable. I then swapped them back to the previous set up and again nothing is able to be read.

Any ideas as to what is going on?
 
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There are two decoders because each decoder is controlling one motor. - The 55021 is only designed to support the load of a single motor.
One decoder will also be programmed to control the lights etc. - This will be the decoder with the 55026 cable connected to it.

The decoders will probably have four wires soldered to the end.. Brown and white are from the track, and the green and yellow go to the motor..
If you remove the brown and white wires from the pins on the main board, you will isolate that decoder from the track.
**Please note which wire goes where!**

Hope that helps?
 
Thanks Phil. I've now tried every combination of isolated decoder, 55026 connected, both 55021s isolated etc. Sorry but I'm still flummoxed.

Can I connect the brown and white cables from the 55045 (normally connected to the track) to the brown and white of the decoder, and programme it that way?
 
Thanks Phil. I've now tried every combination of isolated decoder, 55026 connected, both 55021s isolated etc. Sorry but I'm still flummoxed.

Can I connect the brown and white cables from the 55045 (normally connected to the track) to the brown and white of the decoder, and programme it that way?

Yes you can. Keep the other two wires from the decoder (Green & Yellow) connected to the loco (so that it provides a load for feedback to the programming module),
 
OK, tried the direct connection to the decoder, with the green and yellow left connected to the main board but still it reads 'EPROM not readable'. Could this mean the decoders are toast?
 
OK, tried the direct connection to the decoder, with the green and yellow left connected to the main board but still it reads 'EPROM not readable'. Could this mean the decoders are toast?

It may be a silly question, but have you actually put the loco on the track and tried it? If both decoders are still set to the default address 3, just see if it runs, on either DCC or analogue (it should work on both of course)?
Did you set the DIP switches to the DCC position?

Jon.
 
Jon, no not yet. My MTS package has just arrived, hence the go at programming and fitting decoders. My layout is currently analogue, so I'll try it out in that mode, with the decoders fitted. Once I get the Central Station etc fitted, I'll see what happens. Good suggerstion, thanks.

Mike.
 
PLEASE!
Be very careful with this.. Though the analogue electronics *should* limit the voltage to the lights..
If they are very bright, when you first put the loco on the track, limit how long you have the loco powered else you could blow the bulbs. - Decoders default to full track-voltage on the lighting outputs.

If you put it on an analogue track (or piece of rail on rollers) you should be able to make it run at a low enough voltage to not blow the bulbs.
 
Thanks Phil. I'll put a voltmeter on the track and take it up from 0 until something moves, or not.
 
Update. I had a third, used 55021 with the wires snipped short, which I have just put in my track cleaning engine (piece of cake by the way). I put the engine on my programming track and hey-presto, it was read and I changed the loco address successfully. I then thought about swapping in the other 2 x 55021s from the Garratt and testing them on this loco.

Both of them failed to be read, both came back with the 'EPROM not readable'. Should I now conclude that both of these decoders are dead?
 
it could be that they are toast. The 55021 is a fairly old decoder now - where did you get two from?
It seems more popular to use one larger decoder these days.
 
They came as a part of a second hand package but were, I believe, unused; I had to crimp the connecters on the ends of the wires.

Thanks for the help.
 
They came as a part of a second hand package but were, I believe, unused; I had to crimp the connecters on the ends of the wires.

Thanks for the help.

Can you check for continuity from the pads on the decoder to your crimps? - It would only need one dodgy crimp to stop this working.

**Of course, you may have crimped many connections in your time, if so I apologise.
 
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