Hello all,
I have a well-used but revered Marklin ICE-1 "Elizabeth" 3750 train set that I like to run on my Swiss digital layout. Yesterday, it faltered while running, then went to full throttle, and gave off a burning smell in the front motor unit. I quickly took it off the layout, let it rest, and re-tried running... same consequence. I cannot control it with my usual digital controller (IB). I suspect that the original Marklin decoder gave up the ghost and the motor is operating as it would on an analog layout?? Anyhow, I have a spare ESU Lokpilot V4 that I would like to install in it, but believe I will also need to replace the PC boards (front and rear?). There is only one motor (front), but a device in the rear driving car controls the lighting, forward and reverse. Has anyone had any experience in upgrading this unit? Any help would be much appreciated.
Thanks

Jeff

Jeff,

The 3750 has a 6080 decoder. I have not had any burnout problems with my older decoders, only with newer fx and mfx socket ones, which could be easily replaced.
You should be able to determine whether the decoder has burnt or whether the burnt smell comes from the rotor, brushes or wires. Are there burn marks on the decoder?

I would expect that a burnt decoder would simply cease operating and not operate as an analog unit. Have you tried changing the address settings (dip switches) and see if it will operate on another address.
Try setting switch 1 to on and the rest to off.
The unit in the rear is probably a relay that allows the trainset to select the power from the front slider. This would probably remain if you were to replace the main decoder so that the power still comes from the leading slider.

How close is Bedford to Intervale? Can you take the lok to Hartmann and have them check it out?

Regards

Mike C

Good News... I just tore out the electronics in both cars and replaced them with a LokPilot V4, and wanted to let others know that it can be done. It's not quite the same in operation, as I "hard wired" the directional lights by removing the red lamp from the driving car, and the white lamp from the trailing car, but I never run the unit in reverse on my layout anyway! The motor works fine and seems to have better start-up and slow-moving control. I wired all the lights to the F0 function and now plan to update the car lighting for LED lamps to reduce the draw on the new decoder. All in all, I am pleased that I won't have to use the ICE for a static display. Thanks again for your help!
Jeff

Wiring the car lamps with one side to chassis ground (essentially the track rails) will cause flicker in the lamps. The only way to correct that is to wire to the blue wire instead of ground.
When you connect the second car, you say it does not light, does the car before it go out too? If so, the load is too great, but I can't imagine that with just two cars and LEDs for light. If not, then something is wrong in the wiring to the added car or in the car you are coupling to.

I have this set and have kicked around putting sound in it, but as I'm Era 3, it doesn't seem to happen. I have thought about what I would do though:
1) Keep the axle switch in the unpowered loco to operate the head and tail lamps just as it came from Marklin. Power for those lamps would always come from the slider in that unit.
2) Keep one of the coupler connections as the rear slider (probably already is) and use ESU's change over relay (51966) to mount a 21 pin decoder and control where the power feeds the decoder. This way the lead slider is always the loco power.
3) Use ESU's 51963 miniature relay to switch the center rail to the second connection in the couplers and provide power to the car lamps. The relay coil would be operated on decoder aux 1 so the lights would be switchable. Since the car lamp power switched through the relay contact would be center rail and not through the decoder, you can use the ground connection in each car for the other side of the lamps and not get flicker

This would achieve what I would want and I would be able to use the factory couplers with the two electrical connections.

A cool day and nothing from the postman have conspired together and I have started on the conversion. This is actually my son's 3770 ICE-1 set. He runs it more than I do my 3750 set.

What I have learned:
1. Red is indeed the power feed from the rear (unpowered) unit to the front (powered) unit.
It passes through the coaches without any connection to the coach lamps.
2. Yellow is the feed backward to the coach lights and head/taillamps in the unpowered unit.
3. Each coach has a seperate interior lamp connection to ground via one truck set.

This is the unmodified unpowered unit.



This is the electrical changes I have performed to the unpowered unit, relocating the connection points for the orange and brown wires. The rear slider is now sole power supply to the unpowered unit's lamps. The rear slider will also still feed power to the powered unit via the red coupler connection. Through the 51966 slider changeover, power will be supplied to the decoder from the forward slider depending on direction of travel. Now I can use the yellow coupler wire to switch the coach lamps on and off and still have functional lamps in the unpowered unit. No modification is required to the coaches. Very good news as I have about 16 intermediate cars.



This is where I am at the moment with the powered unit. The 20mm speaker is installed and the old decoder removed.





I have the 51966 slider changeover/21 pin decoder mount board and 51963 relay ordered. From this point it will be a simple decoder install using the instructions from the 51966 circuit board. The 51963 relay will switch the power to the coach lamps via the yellow coupler wire from the (live) slider as I described above, eliminating lamp flicker without the need for the blue connection from the decoder. Also good news as the coupler only provides two electrical connections.

I will post more pictures once I have the items in hand.

Edited at: by user 21 April 2013 15:51:13(UTC)  | Reason: Clarify some steps

I've received the 51966 changeover circuit board and have made some additional progress. I am still waiting for the small relay and sound decoder, but I have been able to get it close to finished using a standard LokPilot to test the function of the changeover board and my wiring.
I purchased a rear (unpowered) unit circuit board so I could keep the function of switching between the slider and pantograph for the front as well as the rear unit. You do not really need this, but it was something I wanted.
I have used ESU's standard color code for the wiring.

This is the back side of the changeover circuit board. On the bottom left is the signal ground (blue) for both lights in the powered unit. The yellow goes to the red lamp in the powered unit. On the top right is the white wire that feeds to the headlamp in the powered unit. The blue on the top right is the signal ground that will go to one side of the micro relay that will switch the coach lamps on and off. The orange and grey at center, bottom left are the motor leads. Orange is (+) and grey is (-). I took them to the circuit board so I could use the existing motor leads that were removed from the original decoder. The black wire bridging both "left" terminals on the top left is the wire that ultimately goes to both rails. It goes to a point on the circuit board that ends at one of the screws to mount the board. The red wire on the top left is the feed from the rear slider. The red wire just to the right of that, by the terminal marked "right", is the slider from the front unit. The red wire at about center top is soldered to the point that feeds the red to the decoder. I will use this wire as the hot feed to the micro relay. It will switch through the relay and then feed power to the coupler yellow wire, lighting the coach lamps. Not shown is the connection to the speaker. They are the two solder pads just above the orange and grey motor leads.



This is the front side of the circuit board. The board did not provide a solder pad for Aux 1, so I soldered this green wire to that point. It will be the switched wire that feeds the coil of the micro relay along with the blue wire described above, located top right in that picture. The red wire described above, at about center top will switch through the relay to the yellow wire of the coupler, lighting the coach lamps.



This is an overall shot of the top of the Marklin circuit board that would normally have been in the unpowered unit. This is a spare I bought from some one parting out a 3770 set. The connection at the top left is the feed from the front unit slider. This is Marklin's wire that was desoldered from the original decoder. Below that at the bottom left is the wire that feeds to the front slider connection on the changeover board. This is the wire that went to the terminal by the word "right". Below that at the very bottom left is the red wire from the coupler. It goes to the rear unit's slider. That circuit passes through the Marklin circuit board to the bottom right side. The red wire soldered there is the red wire that was at the very top left of the 51966 changeover board. The point marked "M-" is the grey motor lead from the changeover board. If you follow the foil you will see it goes to green wire feeding the motor. This green is the original marklin wire. The point marked "M+" is the orange wire from the changeover decoder. That foil leads to the original blue wire Marklin used for the motor. Just to the right of the "k" in "blk" is the black wire from the changeover board. That foil goes to the mounting screw at the top left.



These next two pictures just show a closer detail of the connections at each end of the Marklin circuit board.





I still have four connections to make to the micro relay. The green Aux 1 output and the blue wire that will operate the relay coil and the red wire that is center rail power that will switch to yellow coupler for the coach lamps. I have proven the green and blue work by temporarily solder a lamp in and switching it on and off. I also used a lamp to prove the red wire soldered to the top center of the changeover board will be live and will get switched to the slider that is at the front depending on direction of travel.

A lot to wade through, but if you want to do it, just follow my directions and do each connection one at a time.

Matt

The now completed decoder installation with the micro relay.



Works like a charm. I am quite happy with how it turned out.

Wiring diagram for the 51966 changeover circuit board/21 pin decoder mount:

Bump to keep alive so PJMärklin can use the conversion instructions for his 3071 and ICE.

It appears ten pages is the max for the digital section and then old posts appear to be lost. Is this correct? This thread was two posts away from the edge.

Oops!, need to re-post

Hello John,

Thank you for your kind comments,

Regards and Best Wishes for a Happy Christmas,


PJ

Thanks again for all your help Matt.

Next is the 3071 !

Best Wishes for a Happy Christmas,

Regards,

Philip