the TCM is separate from the engine ECM so the engine casn start and run perfect as well as the high idle switches work.. it sounds like the J1939 data link from the TCM to the shift pad is dead.. the Cat eyes mean the shift pad cant see the TCM.. (hence why you csnt read nay codes from it). I cant remember if you have servicemaxx. if you do you should see when you first start servicemaxx up in the lower box on the screen you should see the J1708 and J1939 modules both.. you would see a TCM and a shift pad listed..



there are "versions" of DOC that can be had. im assuming you have the nexiq or clone device? again I cant remember..



the wires for the J1939 link "should" be yellow / green .. on navistar usually are going into round 3 pin connectors as they traverse the harness.. my first attempt would be to just reboot the whole bus.. (disconnect the batteries completely for 5-10 minutes and then reconnect and see what happens.

Hi Chris,

sorry to bother you but I need a helping hand from someone who knows how to troubleshoot.

So I got a new problem with my wtec3 push pad.
Bus starts ok but when I try to shift into gear, I get cat eyes and check trans light turns on.
When I depress both the up and down button one time so I can pull codes, nothing happens.

I'm working on the assumption the tcu is good because it starts up and the high idle switch does work ok.

How else can I pull codes on the tranny? is there a version of allison doc that is available without subscription?

I guess I'm going under the bus today to check on the physical wiring.

Any help would be greatly appreciated...

ed..