Allison 5sp: Getting a shift range inhibited message.

[Henry95]

So it snowed here last night and did a little drifting on my way to the grandparents. Nothing more then normal. Had a clunk noise when I left home but though it was just frozen breaks. Now I can put it in drive start to move give it abit of throttle to get going and in pops into neutral and get a shift range inhibited message. I don't have my scan tool with me as one off my brothers has it. My cts doesn't show any relevant codes.


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[Henry95]

List of codes just popped up.
Po401
Po404
Po405
Po500
Po700
Po1404
I know that the 400 are my egr deletes codes just haven't had time to take it to get tuned. I am going to see if I can get ahold of my mac scan tool so I can get a proper list of codes for everyone. Getting a service brake system message with abs light. Also I had just put it in 4wd when this happened.


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[Blackmax123]

Dig a little deeper into the PO500 code..

 

[Henry95]

Dig a little deeper into the PO500 code..

I can't get ahold of my mac scan tool as it's 2 hrs away.


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[Henry95]

Gonna pull the rear Speed sensor in the t case and inspect it. Brother had similar issue in his truck.


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[Henry95]

Gonna pull the rear Speed sensor in the t case and inspect it. Brother had similar issue in his truck.


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[Mike L.]

Shift range inhibited happens when the turbine speed sensor is still reading revolutions on the front rotating assembly when you are stopped and in gear. What you did didn't hurt the speed sensor. There is a reason you didn't get gear train pull down at a stop. ( By that I mean the converter turbine attached to the input shaft needs to be stopped ) A damaged clutch pack usually causes that or a transfer case problem affecting the exciter wheel.

 

[Henry95]

Shift range inhibited happens when the turbine speed sensor is still reading revolutions on the front rotating assembly when you are stopped and in gear. What you did didn't hurt the speed sensor. There is a reason you didn't get gear train pull down at a stop. ( By that I mean the converter turbine attached to the input shaft needs to be stopped ) A damaged clutch pack usually causes that or a transfer case problem affecting the exciter wheel.

Thanks for the input Mike. I want to cross the t case off the list before I take it to a trans shop. What should I be looking for in the tcase. I don't have a pump rub fix kit in it. But there was no hole in the rear case half last time I was under it. Had to go to the hospital after that so tomorrow I am going to check for a hole. The trans fluid didn't smell to bad either. Because this happened instantly after I put it in 4 I am inclined to believe the t case has a role in this.


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[Henry95]

Can someone post a diagram of sensors for the tcase and trans. I found wires that have to be ripped away from one it's not the encoder, output sensor on the back of tcase. Turbine sensor or input speed sensor.


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[Henry95]

I feel retarded that I can't find it but I have a IV in one arm for hospital shit.


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[clrussell]

Give me a few

 

[clrussell]

This is for an 05 Lly.. Just guessed since you have egr listed..

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[Henry95]

Thanks the harness they are out of comes of the frame to the tcase. It was rapt around the front drive shaft some how. Sorry but I am not good with that diagram.


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[clrussell]

Thanks the harness they are out of comes of the frame to the tcase. It was rapt around the front drive shaft some how. Sorry but I am not good with that diagram.


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Far left two wires in that diagram.

Don't know what other kinda diagram you can find

 

[Henry95]

Well the harness goes to the rear speed sensor(vss is what gm called it) another part goes to the encoder shifter for the tcase then I have no clue where the other 2 wires go that are ripped out of a sensor.


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[Henry95]

Found it. Fixed


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[aking]

I am getting this Shift Range Inhibited Message as well, but I only have 1 code which is PO872 which its something about Trans Temp Sensor/Switch C Circuit Low.

So I should be checking the speed sensor as well? First I need to find it.

Any ideas?

 

[Mike L.]

I am getting this Shift Range Inhibited Message as well, but I only have 1 code which is PO872 which its something about Trans Temp Sensor/Switch C Circuit Low.

So I should be checking the speed sensor as well? First I need to find it.

Any ideas?

Post some history on your truck and leave nothing out. Shift range inhibited means the turbine speed sensor did not come to zero rpm when the truck came to a stop. Many reasons that can happen.

 

[aking]

Post some history on your truck and leave nothing out. Shift range inhibited means the turbine speed sensor did not come to zero rpm when the truck came to a stop. Many reasons that can happen.

Ok, I thought I read before that the code means there may be a stuck "E" valve that may need to be cleaned and reamed out. My next steps were going to be pull the spin on filter and check for debris, pull the pan, check fluid, change filter and clean the magnets. Then pull the valve body, disassemble and check for burs/debris, clean and reassemble the valves.

Is that a good place to start?