[Taz Holliday]

I usually let truck warm up 10 mins or so before driving. This morning i didnt have that much time. Ran maybe 4 minutes at most. Got down the road 2 miles and went into neutral on its own and the D started Flashing on and off and it wouldnt move a bit. Switched to reverse and same thing. Let it sit for about 5 mins and started it and acted perfectly and drove it. Went home let it set 4 hours or so. Start it up after a little warm up 7 or 8 mins and runs perfectly. The temp here today was about 42 degrees F. Check engine light came on and i scanned it with my cheapo diag tool. showing codes 877, 848, 700. Thanks guys 919 438 4338

any suggestion or similar happen to anyone? please let me know thanks!

Raleigh NC

 

[Taz Holliday]

2016 with 48k miles.

 

[oak1971]

High trans temp at sensor
Low trans pressure circiut
DTransmission Control System Malfunction

What causes the P0700 code?
Faulty transmission control module
Transmission valve body fault
Shift solenoid issues
Open or short in the wiring harness

What causes the P0848 code?
Some common causes of a P0848 trouble code include a faulty transmission fluid pressure sensor, bad electronic pressure control solenoid, and blockage within the hydraulic lines of the transmission. Mechanical failure of the transmission can also lead to the storage of this code by the PCM. Mechanical failure can result from a low fluid condition or dirty and contaminated fluid within the transmission. A low fluid condition or dirty transmission fluid can also cause the PCM to store the trouble code. Though rare, another culprit could be the PCM itself.

What causes the PO877 code?

Possible causes Faulty Transmission Fluid Pressure Sensor/Switch 'D'
Transmission Fluid Pressure Sensor/Switch 'D'
harness is open or shorted
Transmission Fluid Pressure Sensor/Switch 'D' circuit poor electrical connection


Not a mechanic, just mechanically maligned.

 

[Taz Holliday]

thx man. anyone else ever have or see this problem?

 

[JimmyD]

Just went through something very similar except my tranny would not shift out of first gear.

Bad TCM.

 

[KenW56148]

Mine did this just today. CEL is still on. Got it home. I don’t have a scanner so into the Dealership for diagnosing and whatever. 2016 30,200 miles.

 

[cdfinney]

Mine did this just today. CEL is still on. Got it home. I don’t have a scanner so into the Dealership for diagnosing and whatever. 2016 30,200 miles.

Mine did it today. Had 3 stops at stores came out of the last one and wouldnt go into gear forward or reverse. Had to have it towed to the dealer. Truck only has 8k on it.

 

[KenW56148]

Update: Dealerships tech stated found fluid low. No leaks. Apparently I have not checked fluid properly...... according to them. (Big note of non OEM filter on vehicle).

 

[cdfinney]

Mine did it today. Had 3 stops at stores came out of the last one and wouldnt go into gear forward or reverse. Had to have it towed to the dealer. Truck only has 8k on it.

Slight update as the dealers diesel techs had some days off. It looks like the issue is internal to the transmission. The dealer has already floated the idea of a new one. Supposedly was taken apart today, but never heard back.

 

[Trucklover63]

Happened on mine in the first 10K miles. They rebuilt the pump on the Allison. Up to 70K now and it has never happened again.

 

[cdfinney]

Another update. Dealer calls me and they cant find any codes??? While I was waiting for a tow I get email from onstar to have my truck serviced within the next 24 hrs. How can there be no codes I ask. He tells me he cant do any work on the truck without any codes. Then states they will have a meeting about my issues and get back to me at 815am. Big surprise no call at that time. He does call a few hours later to tell me they're having my truck towed back to the dealership. So I'm 2 weeks without my truck and they are just now ordering the transmission module, but it wont be in for 4 days. I HATE the dealership in Concord Ca. I have no faith that they will fix this truck.

 

[JimmyD]

I feel for ya.

It is very hard to believe that it takes 4 days to get the module. For all that I know, Amazon probably has one for overnight delivery.

 

[cdfinney]

I feel for ya.

It is very hard to believe that it takes 4 days to get the module. For all that I know, Amazon probably has one for overnight delivery.

Final update. Called GM customer service on Thursday. Long story, but my dealer lied to them. Truck had error codes PO796 and PO762. I get a call from dealer yesterday morning and my truck is fixed. Glad to have it back.

 

[Trucklover63]

Final update. Called GM customer service on Thursday. Long story, but my dealer lied to them. Truck had error codes PO796 and PO762. I get a call from dealer yesterday morning and my truck is fixed. Glad to have it back.

WTF?????

Glad you have it back but what is up with your dealer!

 

[JimmyD]

Time to find another dealer.

 

[cdfinney]

Time to find another dealer.

The Dealer was the closet one to where my truck broke down. I definitely wont be back if I can help it.

 

[deez112]

Hey I'm having somewhat same problems! Until I deleted, it happened twice. Then after delete, never happened again! Now having trans issues! It began very vague. But now, it's bad! When putting the truck in reverse, it's fine! But, once I let off the brake, there are one or two loud clunks. Used to, the sound was sometimes hard to hear and only when going into reverse and letting off the brake. But, it has gotten louder and now is doing it "on/off" when upshifting. Usually 1-3
2016 2500HD LML
92k miles
Efi live
Fass lift pump 165gph
G&r sump
Egr delete

 

[deez112]

Bump