Replacing the Transmission Selector

[Ambeihl]

I have purchased a replacement transmission selector and want to get it installed soon. Before I do so I want to check all the pins to make sure that its not going to burn up another controller. I had found a pin out guide but I can't seem to find it again. I am looking for someone with experience with this and anything I should look for before I put the controller back in.

Things I have done so far
1. Removed the cable from the cab to transmission and inspected for any exposed wiring.
2. Inspected behind the instrument cluster for exposed wiring.



Sent from my iPhone using Tapatalk Pro

 

[Suprman]

I have seen wires cut and sticking out maybe 6-8 inches down on the harness from the controller. They should be individually taped off. Add a good ground from chassis to trans control body. Where the harness passes thru the dash there is supposed to be plastic protectors so the sheet metal dosnt wear thru the wire but they get brittle over years and fall off. Sometimes water dripping in over time kills them. The lights above the windshield are a culprit there. You can check the trans body harness it comes out the drivers side hump and along the drivers frame rail. Crossing over the trans and mates with a pigtail that comes off the trans a bit.

 

[NDT]

I have been down this road. What year is your truck? 97 and before is Wtec 2, 98 and after Wtec 3. The Allison diagnostic manual with the pin outs and ohm values does not seem to be on the 'net anymore, but I saved a copy and will post it here tonight.

 

[Ambeihl]

It is a 1998 m1078


Sent from my iPhone using Tapatalk Pro

 

[Suprman]

Wtec 3 you just pull the dash panel and swap the keypad. The tcm is under the passenger dash.