Allison TRANS 3000/4000 not shifting, stuck in gear codes p0961 p0973 p097A diagnose - repair HX

[@hddm3]

You are pure gold my man. We need to clone you. Every shop needs you

[@genghiscarnage1433]

Nice diagnosing mate. Gotta be thorough before unloading the parts cannon 😂 🇦🇺

[@AcousticHills]

Thanks and ain't that the truth! 😆

[@Humboldtcounty707]

Hey, I have this code as well as incorrect 1st gear and second gear ratio codes. I'm the third guy to work on this truck. Believe tcm and the whole tcm loom was replaced by previous mechanics. First week at a new shop and they are giving me everyone else's nightmares. Any help would be appreciated! ABS light is on as well. Could that, or a wheel speed sensor be connected? I also noticed that the D on the shifter doesn't light up like the rest of the gears do. Thanks for your videos!!!

[@AcousticHills]

Hey there. Those 1st and 2nd gear ratio codes indicate bad speed sensor signals. Check the wiring for all three sensors. If good, I would replace all 3 speed sensors. Yea it sucks taking over other people's handy work. Good luck!

[@AcousticHills]

I'm talking about transmission speed sensors. ABS will not cause those codes.

[@Humboldtcounty707]

Right, I figured. I was just hoping it got some data from the wheel speed sensors. I had a feeling it wouldn't be that easy. You think I should focus on the speed sensors before the solenoid code? Thanks for the reply!

[@AcousticHills]

@@Humboldtcounty707 gotcha. If you got solenoid codes also, I would remove the TCM connector and ohm out each solenoid AND speed sensor to test the complete wiring of the harness and internal trans. It doesn't matter which you check first, speed sensors and solenoids will have to be addressed. Possibly clear the codes and test drive, then diagnose whichever comes back first. Sounding like a right mess. Thankfully the wiring on these are simple. Test main harness and then internal for solenoids.

[@Humboldtcounty707]

Right on, will do. Having the same software as you do in your video should make that fairly easy. Thanks again for taking the time to reply!!

[@hddm3]

Happens everytime. lol.