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bambamzj
02-22-2005, 02:40 PM
I have a 95 4.0 with the 42re

It has been in limp mode for awhile. I have done a spill and fill and replaced the filter, the fluid looked ok before this. No shavings or metallic flakes were evident in the fluid, filled and checked hot in neutral.

The LED on the over drive switch in not working, not sure if this is related to the limp mode or not. Being a 95 it has a seperate Transmission Control Module. Does anyone know how to check this?

I know you can get codes from the LED on the over drive switch using the same key on/off trick as for engine codes. I dont know if I need to replace the switch or if it could be my TCM is dead and thus making the switch and light inoperative. Any ideas?

For reference I can 2-3 shift manually but if left alone its always in 3rd.


EDIT:
I found a schematic for the TCM

http://www.imagestation.com/album/?id=2130358898

Look at the second image, as noted (in red) the 15 amp mini fuse in the fuse block keeps blowing. This is the circuit for the OD on/off switch ... if you follow the circuit it leads through the switch to the TCM. I have read that the TCM (O/D off lamp driver) acts as a ground. Would this lead to the fuse blowing or do you think that it is a short before the fuse ...ie: going from the fuse block to the ignition switch.

Thanks

Krawlfish
05-17-2005, 07:23 PM
I HATE MY TRANSMISSION TOO! i have a 95.. i bout it off my buddy and he had at least 2 put in.. both times they messed up they had the same deal goin on.. shiftin with the shifter not by itself.. he ended up goin back and gettin it fixed again.. and now i am the lucky one who gets to deal with it.. .but now i have different problems.. sometimes its fine.. sometimes it shifts hard.. sometimes when i go around turns at a slow speed and then accelerate again it starts to jump(kinda).. i hate it.. i also think i am havin problem in my transfercase too though.. it clunks sometimes when it shifts.. and i know its in there...

bambamzj
08-20-2005, 05:50 PM
***UPDATE***

Well I ran a DRB scanner on it and it could not comunicate with the TCM so I swapped in a known working TCM and there was no change. After about a month of asking around for a powertrain manual my buddy tracked one down (another tech had taken it home). With manual in hand I ran a few voltage/continuity tests, as described, and tracked the problem down to a short to ground (big suprise lol). The power feed for the TCM was corrioded. Easy fix and now I have a working trans again !!