Service 4WD Light

aggietke00 · April 13, 2019

I wanted to see if anyone is having an issue with the dash saying Service 4WD. I've got a 2019 AT4 with 12,500 miles. This first instance occurred at around 3k miles. Whenever the truck is started the "Service 4WD" light would come on. Took it into the dealership, they had it for a week and said they replaced the transfer case actuator motor and all would be good. A few months later at about 10k miles it happens again. This time I take it in they perform some computer updates and say that should take care of it. Now two weeks later it's back on for a third time and comes on every time the truck starts.

The other thing that happens is that the parking brake automatically engages every-time the truck is put in park. When it is operating properly the parking brake typically will only automatically engage when I am parked on an incline, unless I manually engage it.

Any thoughts or ideas would be appreciated.

ShamrockShooter · April 15, 2019

What is the lemon law in your state? Usually it is 3 or 4 attempts and you get a full refund.

Sent from my Pixel 2 using Tapatalk

Jponders · August 20, 2019

We have one doing the same thing. Done it at 2,000 miles and again at 3,000 miles.

Trail Boss · November 11, 2019

Same issue... 2019 Custom Trail Boss... @1800 miles, towed to dealer as parking brake would not disengage (computer reprogrammed); 4100 miles, service 4wd and parking brake engaged, was able to get electronic brake to disengage (been at dealer for 2 weeks, replacing actuator and contacts). Was given a loaner vehicle. Hoping to get vehicle back soon and that this fix works!

11/16/19 -- vehicle still at dealer, waiting on "new connectors"!!!

Edited November 17, 2019 by Trail Boss
Update

Chris I · November 12, 2019

Happening to me at this very moment. I honked the horn at some lady who about turned into me and the service 4wd notice come up. Then I pulled over and turned the truck off and it is saying the parking brake is engaged. 2019 AT4 with 2409 miles.

DGate9 · November 15, 2019

Same issue exactly, right down to the parking brake engaging. It started at 2000kms and it’s done it half a dozen times since. GM is acting like they have never heard of this but obviously it’s a thing. My friend got the exact same truck a month later than I did and his just did it last week. Taking it in again next week even though once again it has corrected itself.

tinbad · November 16, 2019

Today I was backing up a slippery/steep driveway - tried to put in 4lo and service 4wd light came on, 5500 miles.

tinbad · November 18, 2019

So today I start the truck, put it in drive and guess what... the “service 4wd” message goes away. Drove it 200 miles back home and message didn’t come back. Go figure.. fingers crossed it was just a one time glitch.

Ksalway · November 19, 2019

My 19 RST just did this to me this morning, 4wd symbol on the dash Aldo turned red. Anyone have a fix for this yet ?

Ksalway · November 25, 2019

No one has had this problem and gotten a resolution?

Colossus · November 26, 2019

Resolution: Warranty repair.

CuseGMC · December 5, 2019

I have a 2019 GMC Sierra 1500 SLE with 900miles on it did the same thing. Service 4WD message and parking brake. Going to bring it in to get serviced tomorrow. Does anyone know what component(s) need to be replaced?

KyAT4 · December 15, 2019

Any information on what the fix was for this yet? I have a 19 AT4 with the performance package and my Service 4WD light came on randomly when I started the truck in the morning. My wife typically leaves the truck in the Auto AWD setting. When the light came on the truck was acting like it was in 4WD and none of the buttons were working to put it into 2WD. Therefore on dry pavement I had to make it home on a Sunday about 100km and book the truck in. The dealership got the truck into 2WD and said the TCCM transfer case control module needs to be replaced and it could be a while for the part to come in. They said keep the truck in 2WD and do not use 4WD. Well I live in Canada and we had a snow storm last night and I was not pleased to be told not to use the 4WD on a truck a bought 2 months ago.

Did a new TCCM fix the issue for anyone?

Ksalway · December 24, 2019

On 12/15/2019 at 1:37 PM, KyAT4 said:

Any information on what the fix was for this yet? I have a 19 AT4 with the performance package and my Service 4WD light came on randomly when I started the truck in the morning. My wife typically leaves the truck in the Auto AWD setting. When the light came on the truck was acting like it was in 4WD and none of the buttons were working to put it into 2WD. Therefore on dry pavement I had to make it home on a Sunday about 100km and book the truck in. The dealership got the truck into 2WD and said the TCCM transfer case control module needs to be replaced and it could be a while for the part to come in. They said keep the truck in 2WD and do not use 4WD. Well I live in Canada and we had a snow storm last night and I was not pleased to be told not to use the 4WD on a truck a bought 2 months ago.

Did a new TCCM fix the issue for anyone?

Scheduled an appointment for mine can’t get it in until December 30th. Any luck on your part coming in? The service 4wd message has come on 4 times now but clears itself

Snakes709 · December 25, 2019

Mine has given me this message 4 times. Brought it in 3 times. Same code each time and each time they do a system relearn, clear the code and give it back. If it happens again ill be filing a claim with gmc.