Weird thing happened while in 4-low

Mossyoakglock · July 6, 2014

Today I was in 4 low going up a pretty steep grass hill and had to stop for about 3-4 minutes. While I was stopped, my tach and all gauges went to zero and my service 4 wheel drive message came on, I even think the truck was still running (I was still in drive)

So I turned off the truck and put it in park and started it back up. It started up and all the gauges were normal and then the tach went right back to zero but the truck was still running. I put it in drive and everything came back normal.

I even had my wife get in and I made sure that it engaged 4-Hi and 4-Low and that the driveshaft was turning in both.4-wheel drive functioned fine as well.

Any idea what might have happened? 4-wheel drive actuator going out? I got no codes or anything else other than the Service four wheel drive message.

gmtech4 · July 7, 2014

Sorry bud ,but the service message means there IS a code in the TCCM , it needs to be scanned by a scanner capable of reading them ,

You can't guess as to the problem ,

Each code can have several possibilities

Mossyoakglock · July 7, 2014

I've got a simple code reader. Will that work or will I need a more advanced one? Can I take it somewhere like Fireatone or is this a dealer only thing?

Mossyoakglock · July 7, 2014

can't believe what I just saw. At the dealer getting the code scanned and was watching the girl move my truck. She gets in and starts it and I see her mashing on the parking brake. A service writer comes over and opens the door and the he mashes on the parking brake trying to get it to release. Really? You work at the dealer and you don't know there is a latch? The girl is maybe 18 and they is in his 40's. She just starts laughing like its funny. I was in my way into the service bay to show them when they finally got smart enough to figure it out.

txab · July 7, 2014

So what did you find out about your problem?

Mossyoakglock · July 7, 2014

No hard codes in the system, just history codes. They didn't give the actual code numbers, just the description so the code numbers are what I could find online.

Lost Communication with EBCM - U0141

Lost Communication with TCM - U0101

Lost Communication with BCM - U0140

I do have a Range V8 on the truck and it was plugged in when it happened. I obviously removed it when I went into the dealer because they would need the OBDII port.

Could it have been the Range causing it? Like I said before I had my wife cycle it through 4HI and 4LOW a few times and watched the front driveshaft and it engaged and disengaged every time. I even cycled it through both in the dealership parking lot and everything was good. The problem happened when we first got there and I kept it in 4LOW for the rest of the day (3-4 hours) and did multiple starts, forward and reverse and it never did it again.

I found the below topic while searching.

http://www.gm-trucks.com/forums/topic/150665-aftermarket-devices-plugged-into-data-link-connector/

It makes sense that something plugged in can cause communication issues.

Edit: The tech said they cleared the codes and all systems and tests were passing when they were testing and doing the diagnostics.

MikeNH · July 8, 2014

Seems likely. The communication codes are what others with the Range have reported.

Mossyoakglock · July 8, 2014

I might give Range a call tomorrow and talk with them and see what they say.

txab · July 8, 2014

Have you read through this thread?

http://www.gm-trucks.com/forums/topic/150751-disable-afm-without-tuning/?p=1322424

Mossyoakglock · July 8, 2014

Yea, I've read through that one.

The only post that I saw concerning error messages was on a '14. I have an '08.

If I get the error again and can confirm that it is the Range causing the communication error, I might try to pick up a Diablo or something and disable it that way. That way nothing is in the OBDII port that can cause a communication error.