Help on Old TMCC Board

On the R2LC, your rear coupler is pins 9 and 10.  For your front it is 13 and 14.  On aux tenders I like to put the rear coupler on the tender to pins 13 and 14 and program the tender the same as the locomotive and hit the front coupler to fire the rear coupler.  This was if you hit the rear coupler on the locomotive, you leave the aux tender behind.  If you do my way you leave the train behind and keep the aux tender with the locomotive/tender.

Common is pins 3 and 4..

So Marty,

You suggest soldering directly to the R2LC pins and not to the pins in the harness?  If so, which are the light pins and is pin 1 where the M1 label is?

The common for the couplers and lights is frame ground (wheels).  As Marty correctly points out, that's pins 3 & 4 on the R2LC, but ground is ground anywhere in the chassis.

Got it. So in theory, I could put one lead to ground for all and then use RC, RL, and FC four the other lead so I can use the existing tether?

This is an Aux tender so why are you using a mother board and R2LC  vice a LCRX or other ERR device to control the AUX tender?  On that mother board the silk screen is missing the Grd identification. IF you use a VM to check you probably fine the 2 end pins are 3rd rail and Ground, followed by another ground pin some where in the middle.

I recommend soldering to the base of the pins under the board.  IF at a later date you want to use this mother board with connectors, you will have a problem doing it if soldered to connector pins.  G

I'm guessing he already had the R2LC & MB.  I'd try to scrounge up the connectors for the MB and not solder to it at all.

John, correct.  This auxiliary tender came with TMCC out of the box to control the backup light and the couplers.  I just didn't show the R2LC in the pics.

If it came that way where are all the connectors? Usually they used a LCRX.  Any way what I stated about the silk screen should be correct wrt finding a ground pin there.  SO you have the signal pins coming from R2LC pin out for lights and coupler, and the return is to chassis ground.  G

I've opened a couple of aux tenders that had a full R2LC, including the one he mentions.  They didn't all come with the LCRX.

 (6-28087) Union Pacific TMCC Scale Auxiliary Water Tender (Yellow) #907856

(6-38008) Union Pacific TMCC Scale Auxiliary Water Tender (Greyhound) #907857

Ok, Interesting why some one gutted the connectors.  G

Sorry George, I can't explain why anyone would do that.

This one was gutted because it was converted to 2-rail with scale couplers.  That is why I'm confused by the board.

I guess my point is I still do not understand why folks gut stuff.  Just disconnect coupler. I guess if running DC 2 Rail they would have to unpower everything since TMCC is not DC compatible.  Of course it is their train G

Wouldn't they have to replace the wheelsets at least to run 2-rail?

John, they did. I got some 3-rail wheels and changed them back.  Now I am just waiting on the missing parts from Lionel so I can fully convert it back.