A340H Transfer Stuck in 4Lo after Trans swap

[Mr DNA]

Hey all- after a ~8 year time period away from Toyota 4x4s (well, all 4x4s, sadly) I recently picked up a 94 4Runner with the 3VZE and A340H trans/transfer. I got it at a very good price with low (for the year) miles mainly because the transmission, while completely functional, had a nice crack in the case the leaked fluid like crazy. I got a used trans/transfer with fewer miles and did the swap.

Everything is in, but regardless of how I adjust the transfer linkage it will not come out of 4Lo. If I disconnect the linkage and manually move the lever to 4H or 2H it still is in 4Lo. I don't think the ADD system disconnects as it does not like sharp turns on pavement.

So here's what I think are possible causes:

• Bad connection (I did wrestle with the two 6-pin connectors above the bellhousing when removing the old trans)
• Bad switch or relay
• Bad or not-connected solenoid
• Hydraulic issue in the transfer
• Mechanical issue with the planetary gears, clutch, or brake in the transfer

I have a copy of the FSM and am going to be doing the various voltage and continuity checks this evening. I am also planning to remove the front driveshaft in the meantime so that I can do 20mph test laps around my neighborhood without damaging the transfer or front drivetrain.

If you have some deeper experience with this transmission and have a little insight, I'd sure appreciate your help. Thanks!

 

[Mr DNA]

Update:
I checked the transfer switch- when in 2H there should be no continuity between the three terminals, which says to me that unplugging it should put the truck in 2. I tried that and it was still in 4L. I also checked the status of the wiring connectors and they all appear to be connected properly.
I remember that when I installed the trans I could rotate the front power output, meaning that it was definitely in 2.

I've searched pretty extensively on this and other sites, and while there is plenty of content on the No. 2 or 3 solenoids malfunctioning or instances of the truck not shifting into 4, I was not able to find any where the truck won't shift out of low range.

Again, any help you can provide I sure do appreciate it.