Lionel/ K-Line FM Train Master Motherboard 691-PCB1-072 - Need Wiring Diagram

Here's a page from Lionel Supplement #45 with an engine using that motherboard.

@gunrunnerjohn posted:

Here's a page from Lionel Supplement #45 with an engine using that motherboard.

Thank you John! This helps but it doesn’t show the connections for the smoke unit. Any chance of locating a diagram with a smoke unit?
***Model: K-Line #53 Virginian Train Master K2499-0053CC***
Although, I can probably narrow it down by process of elimination. This loco has 2 DC can motors (no cruise) and smoke unit. The smoke unit’s resistor metered 29 ohms. This unit has a lot of wiring issues. More specifically, the vinyl coating is brittle and  cracking on most of the wiring. I’ve already replaced a bunch of it. It appears the loco was serviced/worked on and someone used the wrong grease (looks like black moly grease) and a lot of it. Through the the years of off-gassing, I believe it degraded the vinyl & plastics. The shell seems a little brittle too. I cleaned most of it out of the trucks & gears and I’ll do a more thorough cleaning later on. As far as the smoke unit goes, my meter is measuring 9VAC/6VDC at the smoke unit’s 3 pin JST connection. I measured +6VDC from the middle pin (blk wire) to chassis ground. The 2 outer pins (grn wire) to chassis ground reads -6VDC. Is the smoke unit getting the negative side of the sine wave in DC?
Thanks,

Dan

The smoke unit should just connect to the smoke output, the smoke fan and heater should be powered from the same source.

The center pin of the 3-pin connector to the smoke unit should be frame ground, and the reading from frame ground to either outside pin should be positive voltage in command mode with smoke on.

The fact that you have negative voltage there suggests the wiring to the smoke unit is backwards, the R2LC-C08 and later should be putting the positive half cycle of the track voltage in command mode.

@gunrunnerjohn posted:

The smoke unit should just connect to the smoke output, the smoke fan and heater should be powered from the same source.

The center pin of the 3-pin connector to the smoke unit should be frame ground, and the reading from frame ground to either outside pin should be positive voltage in command mode with smoke on.

The fact that you have negative voltage there suggests the wiring to the smoke unit is backwards, the R2LC-C08 and later should be putting the positive half cycle of the track voltage in command mode.

John,

You may have hit the nail on the head. I didn’t look to see what version the R2LC is. Maybe someone swapped it out with the wrong one? I’ll take a look again later today. The fact that non of the other smoke units work with it leads me to believe the R2LC is putting out the wrong negative half cycle as you pointed out.
Thanks again!

Dan

@DanVW posted:

You may have hit the nail on the head. I didn’t look to see what version the R2LC is. Maybe someone swapped it out with the wrong one? I’ll take a look again later today. The fact that non of the other smoke units work with it leads me to believe the R2LC is putting out the wrong negative half cycle as you pointed out.

From this description, it sounds like the middle pin is NOT grounded to chassis ground, which is the real problem here.  You should not read any voltage from the middle terminal to frame ground, they should be connected!

@DanVW posted:

As far as the smoke unit goes, my meter is measuring 9VAC/6VDC at the smoke unit’s 3 pin JST connection. I measured +6VDC from the middle pin (blk wire) to chassis ground. The 2 outer pins (grn wire) to chassis ground reads -6VDC. Is the smoke unit getting the negative side of the sine wave in DC?

@gunrunnerjohn posted:

From this description, it sounds like the middle pin is NOT grounded to chassis ground, which is the real problem here.  You should not read any voltage from the middle terminal to frame ground, they should be connected!

John,

I worked on it some more and figured it out. I had to replace a few more wires due to various issues. The brown wire lead to front motor had an internal break so I replaced both leads. The front & rear coupler wires were cracked and frayed. And list goes on... When I finished those, I went back to the smoke unit. I checked the R2LC and confirmed it is a C08. Retested it and again, the heating element was getting hot but still no fan. Stumped, I double checked the voltages with my meter and got the same results. On a hunch, I swapped the R2LC with a known working board. This time, I programmed it as engine 1 but didn’t set the reset code. The fan came on! (Initially, I found a couple resources that stated the code should be set to 6 and that’s what I reset the original board to.) I reset the R2LC to code 6 and fan didn’t work again. Again, reset it to 8 and it’s good. Pulled that one out and reinstalled the original R2LC and set that one to 8 as well. The fan works. So, the next question is: What does the reset code 6 do to the R2LC? Apparently, it reverses the polarity to the smoke unit (it was reading AC & -DC on my meter at the leads). I wonder if code 6 is for AC Pulmor motors? I know both motor types use the same motherboard in the FM’s. What do you think?

Thanks,

Dan

See attached file, six is for engines without a smoke unit.