Green LED Marker Light Intermittent LionMaster UP Challenger

Only the obvious, check the wiring to the lights.   I think there are six screws along the base that drop the sheet metal frame away from the boiler shell.  A couple of plugs and you have it apart.

John - thanks.  I've only ever taken apart my diesels.  (I just have 2 steamers.)  So I was a bit intimidated by how complex getting to the boards on this Challenger might be.  

The wiring did seem obvious.    I was just throwing the question out there to see if a triac (will profess ignorance on exactly which component that is, but I know there's one involved in the lighting circuit) or other board component is notorious for acting up this way before failing completely.  I have noticed for some time that one of the diodes seemed brighter than the other, but just assumed that was a variation in the diodes themselves.

Just to add to what John posted you should find a reference to the screw locations in your owners manual. A possible cause might be the marker light wiring harness contacting the flywheel of the front truck can motor and has worn through the insulation. I would check this area thoroughly.

Rod

Thanks Rod.  I'd looked in the manual but had missed the cab screws.  After your post I went back and looked again.  They are marked on a diagram for the lubrication points.   When I take it apart I'll pay careful attention to the area you've pointed out.  Thanks again.

I doubt this will be a triac if the other lights all work.  The only lighting triacs in that unit will be the headlight and reverse light.  The reverse light output may not be used if it has the wireless tether.  Those makers will be on the headlight circuit or wired to track power I expect.

The problem is stemming from a bad connection on the 10-pin connector along the side edge of the Odyssey motor driver board. That is what is causing the flickering issue! Gunrunnerjohn or others here can help you resolve it from there. He needs a new 2.0 mm spacing wire terminal on the ends of his wire OR solder the leads to the underside of the DCDS where the pins come through and are soldered (not my preferred method, as the next guy who opens this engine up will not be able to separate the shell from the frame!

Mike 

I guess it would have helped to know it has Odyssey.   If that's the case, I suspect Mike is likely correct.  If that was the case, I'd just crimp another pin on the wire, but I suspect most don't have the contacts or the crimp tool.  Sometimes you can gently squeeze the contact "just a little" to make a better connection.  Something like Deoxit D5 will help flaky contacts as well. 

Another route taken by some is to remote the wire and contact from a scrap 2mm Lionel connector and splice it onto the wire and toss the old defective contact.

I really appreciate this info.  My TMCC "fleet" is all of 3 engines, including the Challenger.  So a "box 'o spare parts" is not something I have.  I may see if that's something I can order from Lionel with a few other things like traction tires that I've been meaning to get.

If you want a wire with the proper contact on it, let me know.  Check and see if a bad contact in that connector is actually the issue, I can put the wire in an envelope and send you one.

I took the engine apart today.  As Rod had suggested, it was just 6 screws and the cab came off without incident.  It was easy to find the 10 pin connector Mike mentioned and after removing it I gently released the plastic retention clips on the red and black contacts and pulled them from the connector.  I applied a little additional pressure on the contact crimps and closed up the opening a bit so it gripped the pin tighter.  But after reinserting the contacts and plugging the connector back in this didn't help the flickering LEDs.  

Taking the connector back off I measured the voltage across those 2 pins with the engine on the tracks and track voltage on.  It was varying wildly.  Putting the connector back on and playing with the CAB2 I noticed that the LEDs state (flickering, off or on) was consistent as long as no commands were issued.  The state of the LEDs would change if I reversed direction or blew the whistle etc.  I noticed that at least at one point with the LEDs flickering if I pressed AUX1-3 (steam blowoff sound) the LED would become steady while the sound was playing and then go back to flickering.  Every time I played the blowoff sound the LED would go steady on until the sound ceased and then it would resume flickering.   While this was going on I checked the voltage across the exposed contacts (arrows in photo) and it varied wildly except when the blowoff sound was playing.  While the blowoff was sounding the voltage became a steady 1.4v  There was no flickering or odd behavior at any time from the headlight on the front pilot deck.

Given this additional info, I'm wondering if Mike Reagan would still think this is just a bad connection?  I wonder if the board I circled in the photo (DCDS?) needs to be replaced?  Can I replace just that board?  Given it's a 2004 TMCC Odyssey vintage, I wonder if such a board is even still available.?  I'm also wondering if the most cost effective solution would be powering the LEDs off track power rather than replacing the board.   When they are working the LED's (as well as the headlight on the front pilot deck) seem to be on when track power is present whether you've addressed the engine to start up yet or even after you've shut it down.  So it would appear just powering off track power would be functionally identical to the OEM wiring.  But given the steady on LED voltage across the 2 pins was 1.4v I'm guessing I'm going to need a resistor or something inline between 18-20v track power and the LEDs.  Or perhaps tapping into the power at the light for the firebox glow?

A while back I repaired the markers on a similar vintage TMCC engine by wiring them to the headlight circuit, in parallel with the bulb wiring. This means of course the markers turn off/on with the headlight, which I figured was not a bad thing. This is way cheaper than replacing the DCDS board, which is about $100 as memory serves. I am sure they are readily available. Since the markers are LED's you will need a current limiting resistor in one wire to the markers. I don't have the records of the repair on hand at present, but I recall the resistor was about 720 ohm. Since the LED load is minimal, you will not overload the headlight triac doing this. If you have a few various resistors handy you can experiment with the values. Start high with about 1000 ohms and work down cautiously.

John, can you provide any better detail on what value the resistor ought to be?

Rod

If it's just the class lights, I agree with Rod. I'd just wire them to the headlight circuit.  Put a 1K resistor in series with one of the leads to the LED's.  Connect the cathode side (negative) to the headlight circuit and the anode side (positive) to frame ground and it's job done.  They will be controlled with the headlights with this connection.  You can go lower to about 470 ohms on the resistor, but I don't like the class lights to be brighter than the headlights, so I tend to go big.

Rod,

shoot me an email Monday at mreagan@lionel.com with a number I can reach you at tomorrow.

thanks

mike

John,

I want to make sure I'm doing this correctly.  I've attached a photo of what I think I'm tapping into. I traced the 2 black wires from the headlight on the pilot truck into a bundle of 5 black wires that came up the side of the can motor for the front set of 6 wheels and up into the cab.  The wires went into 2 different connectors and by process of elimination I figured out which of the connectors (circled in red on my photo) had the wires for the headlight.

However, that connector has 3 wires.  Tracing the other side of the connector 2 of the wires go to a 2 pin connector (yellow arrows on my photo) - one red and one black lead.  The other of the 3 wires goes to a completely different connector (blue arrow on my photo).  I'd assume the red and the black that go to the same connector (yellow arrows) are my headlight leads.  (There's an extraneous red arrow in my photo that I just noticed and didn't intend.)

If the above is correct would I come off the red lead that goes to the headlight and attach to a 1K resistor then from the resistor to the red lead for the first LED and then that LED's black lead connects to the red lead for the second LED and then that 2nd LED's black lead goes back to the black lead for the headlight to complete the circuit?  Radio Shack has 3 different 1K resistors.  Would 1 be preferred?  There's a) 1K ohm 1/4-Watt Carbon Film resistor catalog 2711321 b) 1K ohm 1/2-Watt 5% Carbon Film resistor catalog 2711118 and c) 1K ohm 1-Watt Metal Oxide Film resistor catalog 2710153.

On my previous post I meant to add a video of the LEDs weird behavior that seemed to be tied to commands from my CAB2 (in this case multiple presses of AUX1 - #3 for steam blow down. 

I'd see what Mike R. has to say Monday, he may have a simple fix for you.  If not, we can figure out what to wire.   If we go with a resistor, the 1/4w one is fine, no need to go bigger.

Mikado posted:

Rod,

shoot me an email Monday at mreagan@lionel.com with a number I can reach you at tomorrow.

 

thanks

mike

Oh-oh; looks like I may be in serious doggy do-do with Mike R.!

Seriously, I'll send you an email Mike.

Rod

Rod Stewart posted:

Oh-oh; looks like I may be in serious doggy do-do with Mike R.!

 

Nope - Mike R. actually meant to address that to me.  He just responded to my email.  Looks like you're in no doggy do-do at all there Rod.  

Hey guys,

My apologies for the confusion on the posting order! Those class lamps look to me like the wires are connected to the firebox flicker output on the DCDS. The pinouts on the DCDS do a variety of functions depending on the code loaded onto the processor. Everything from firebox flicker to oscillting ditch lights! Has the DCDS ever been replaced to the best of your knowledge? There should be a white sticker on top of the processor that has a code on it "HM5" or "YU1" or "FP6" Knowing what was on that sticker will help me better understand what driver is currently in the loco (and determine if the wires are in fact in the wrong positions!). 

Worst case scenario, as someone above suggested you could always tie the markers to the collectors and ground or the front headlight output, but ONLY IF you install a drop down resistor! Leave the resistor out and I promise they'll never come back on again! LOL. 

Left you a voicemail, give me a shout when you have second.

Thanks,

Mike

I've gotten Mike R. the DCDS processor ID and I'll update here with the outcome, whether that's being able to power the LEDs from a different set of pins on the 10pin DCDS connector or grabbing power from the headlights with a resistor in line.

I've been into Lionel trains all of my life thanks to my grandfather.  I have things from my grandfather's 1950's vintage offerings up to the present.  So I'd previously acquired a few parts from Train America Studios years ago.  And I've picked up quite a bit from Mike R's Lionel YouTube videos more recently.   So, I've known "who" Mike Reagan was for a very long time.  I just never thought I'd get to speak to to him at length on anything.  OMG  He's one class act.  I look forward to meeting him in person down the road.   Count me a fan.

Mike's normally at York, so you get a chance twice a year.

Sounds like you're on your way to fixing this.

gunrunnerjohn posted:

I'd see what Mike R. has to say Monday, he may have a simple fix for you.  If not, we can figure out what to wire.   If we go with a resistor, the 1/4w one is fine, no need to go bigger.

John,

Mike R. reported back there were no other DCDS outputs to drive the markers so the track power is going to be the best solution.   Direct solder connections to the pickups or to the headlight didn't appear to be easily accomplished but I did notice the firebox light was in a wide open location.  It only had a single red wire to it but the screw holding the plastic mount for the socket appeared to be grounded to the frame.  Measuring voltage across the red lead and the mounting screw showed the same 17 volts I was reading between the center and outside rails.   I've posted a picture of this below.

Earlier in this topic you posted "Put a 1K resistor in series with one of the leads to the LED's.  Connect the cathode side (negative) to the headlight circuit and the anode side (positive) to frame ground and it's job done."   Electronics are a new subject for me so I'm asking rather simplistic questions.  I've picked up a 1K ohm 1/4 watt carbon-film resistor from RadioShack.  If I understand correctly the LEDs for the markers have a positive side and a negative side and will only work if wired accordingly.  With a multimeter I've verified that the red wires on the LEDs are the anode/positive side and the black wires are the cathode/negative side.   Based on what I've read the resistor doesn't have a polarity that needs to be followed.  

It seems counterintuitive, but if I understand your instructions I should solder a lead to the positive (red wire) on the firebox light socket and run it to one side of the resistor.  The other side of the resistor would then connect to each of the black wires (cathode side) of the 2 marker LEDs.  The two red wires (anode side) of the 2 marker LEDs would then run back to the frame ground near the firebox light socket.  Is that correct?  (Intuitively it seems like the power would run from the red firebox socket connection through the resistor and then to the RED/anode/positive of the LED instead of the cathode/negative side.  But I'm an electronics newbie and there must be something else here I don't understand.)  

I just wanted to double check my wiring before I apply any current and regret it.

The headlight circuit usually has rectified AC running to it through the lighting triac in command mode.  The firebox light is running directly off track power, so it's pure AC.  The 1K resistor in the circuit will limit the current.  Truthfully, I'd add a diode for reverse voltage protection as well, I use a 1N4003, but any common silicon diode will work.

Thanks to all above, particularly GunRunnerJohn and Mike R, the marker LEDs on my Challenger are now steady once again.  It was a interesting repair in that I learned quite a bit about diodes and resistors in the process.  I had no idea about diode polarity or that a resistor didn't have such polarity. But with some Google research and patient help from folks on the forum I learned some new things.  

In the interest of helping others who might have a problem with LEDs in the future and want to power them off track power I've attached photos of the final solution.  I picked up track power off the firebox light as it was in the open and considerably easier to access than the pickup connections on the trucks.  I followed John's advice and added a diode in series between the positive lead off the firebox light (to the diode's anode side) and a 1K ohm 1/4 watt resistor.  The other side of the resistor went to the anode (positive) side of the marker LEDs (in parallel).  From the cathode side of the marker LEDs (in parallel) back to negative through the frame back at the firebox light.  I used shrink tubing over the positive lead, the diode and the resistor along with disconnects in line on the positive and negative sides of the circuit to allow easy removal of the cab in the future.  

Nice job, and good thinking on the disconnects, I try to do that with anything that connected between the frame and shell, makes maintenance much easier. 

For future use, if you need compact connectors, I use machine pin headers and matching sockets, here's an example.  This is useful in smaller equipment with limited space for extra wiring.  Solder the wires on, apply a little heatshrink tubing, and you have a connector.