Lionel TMCC

One thing to check is the wiring to the run/program switch. If a wire is broken or the switch does not close its contacts you won’t go into program mode, only run.

Pete

As Pete mentioned, check the RUN/PGM switch for any broken wires. What happens when you’re in PGM, power up your track,you address it a number, and hit set? Do you get a whistle acknowledgment that the ID has been set? That’s step # 1 before worrying about resets. If not, like Pete mentions, something could be up with the RUN/PGM portion of the system, broken wire, bad switch, etc, etc,….

Pat

The RUN/PROG switch wires are OK.

When I tried to program the ID, I got no response.

Might be a problem on the other end, motherboard connection or bad contact on the R2LC. You can use an ohmmeter. One lead from the switch goes to chassis ground, the other to pin 22 on the R2LC.

Pete

How do I identify "pin 22"?  Do you have a schematic of the R2LC board?  Is pin 22 one of the pins of the 24-pin connector?  Are there connections where I could see a signal with my oscilloscope?  

Thanks for the suggestion and for any further replies.

Here you go. Pin1 has the square pad. All odd pins are next to the edge. A scope not needed for program / run switch connections. Open you are in run mode. Pin 22 connected to pins 3-4 is Program mode.

Pete

Also, another of the most basic of basic checks when troubleshooting TMCC

Does the headlight blink when TMCC commands are sent - any command, not even one specific to the engine. That was a built in function to validate the R2LC and most other TMCC equipment is getting a valid TMCC signal- when a command is decoded- the headlink blinks as an acknowledgement for validation of operation.

Thanks to Vernon and Pete for your suggestions.  I have checked that the RUN/PROG switch wires are OK with the one going to pin 22 of the R2LC pcb and the other to chassis ground.  I also checked that the antenna wire provided continuity to pin 23.  I did not get a blinking headlight when a TMCC command was sent ... the headlight stayed on steady.  At some point the idling Railsounds started up when I pressed the rear uncoupling button, but I could not repeat this.  Nor could I get the Shut Down sequence to then work.

I tried the blink test with another TMCC engine and found that the headlight would blink with the uncouple commands, but none others, and only when that engine had been addressed.  Does anyone have more particulars about the "blink test".

Remember that the engine works in Conventional Mode.  It has a really great whistle!

Might be a long shot, but try to remove the control boards one at a time and then re-seat them.  I've had issues at times with oxidized pin connections.

If that does not work, do you have a spare R2LC board you can test with? Sound like that board may have failed.

As Dave pointed out, for S&G’s try unseating and reseating the radio board ……do make sure you land it back right where it’s supposed to be, and don’t miss a pin set!…very bad things can happen……Before condemning the radio board, as you’re aware now, pin 22 gets closed to ground to allow programming. Can you verify 22 rings to ground when set in PGM using a multimeter?…..DO NOT have the locomotive powered up when probing!….you can do that test cold……..

Pat