Transmission Position Switch on 3.0

[andrewwynn]

Seems my position switch has failed.

I got a trans failsafe error after the battery went flat from sitting too long, I was able to reset the error but noticed that my dash didn't match my selected gear properly. (Example showing 54 vs D or nothing at all).

Took a while to find the proper submenu in the foxwell NT510 but sure enough found the real-time data from the transmission and the open/close of the four lines are wonky: inconsistent. I'm concerned the problem is actually inside the TCM which would be far easier to replace than the range/position switch which is inside the damn transmission!

Has anybody actually removed one of these ? I have a shop manual but it only includes how to replace the range switch on the V8 where it's external!

It looks like the switch is pinned in with a pair of roll pins and of course I need to drop the bottom off the transmission to get to it. Bringing me to phase two: since I have to remove the transmission fluid and pan, should I put the same fluid back in or replace with new fluid and filter? Until this failure the transmission has been flawless and I push it hard.

I'm considering making an extenal switch box to assign which gear I'm in until I take the transmission apart it's pretty simple BCD coding. I can buy a $5 BCD 4 bit switch and label the magic spots for PRND. Would be a LOT LESS work than dropping the transmission pan!

I can usually get the switch to register properly by shifting in/out of gear until the wiper cleans off the contact but it seems more than just a dirty contact because sometimes a contact is closed when supposed to be open (as if wiper is bent).

I got some really horrible shifts when it first wigged out and I was terrified my transmission was shot but now I'm confident it's either the position switch or the TCM which I've seen on eBay for like $25.