Service 4WD Light

[19Sierra]

I've gotten the message 4 times as well. Each time it happens when going from 4wd or Auto 4wd back to 2wd. Code clears once I start driving again and get a 1/4 mile or so down the road. It happened to come on when I took it in to get the brake recall done. Code disappeared after the recall programming. Will call them tomorrow.

Edited December 26, 2019 by 19Sierra

[Josi De Gracia]

This has happened to me twice on my brand new only got 4k on it now 2019 trailboss service 4wd and now the parking break is being automatically applied now when placed in park, before it only was applied when i pressed the parking break button.

[Snakes709]

3 hours ago, Josi De Gracia said:

This has happened to me twice on my brand new only got 4k on it now 2019 trailboss service 4wd and now the parking break is being automatically applied now when placed in park, before it only was applied when i pressed the parking break button.

Mine did that two. The 2 systems are connected together so when you get the service 4wd message, you will have the park brake automatically apply. 

[Ct1022]

I have a 2019 2500 gmc dealer jas replaced the actuator transfer case module transfer case wire harness and fuse block still getting an intermittent service 4x4 indicator the last 2 times I've picked the truck up from the dealership it indicated service 4wd on start up in there parking lot

[Ksalway]

Anyone have any luck getting a fix for this? The dealership did nothing for me, as they said that they had no codes to go off of and couldn’t replicate the issue. 

[Ksalway]

Light came on yet again last night during a snow storm, getting really frustrating as my dealership keeps giving me the same BS response as they can not diagnose if the light is not on , as it does not store a code...

[Dan V 25]

Mine is at the dealer now. Brought it in for service 4wd and the recalls couple weeks ago. They updated the software and said it would be good. Week later bad snow storm put it in 4 auto and light came back on. So I took it in this past friday and they're waiting for a part. Hopefully it comes in monday. I'm glad I'm not the only one having the problem but disappointed we're having this problem. On a good note I get to drive in the 20 blazer. Probably will be picking one up in a couple of years for the wife. 

[19Sierra]

52 minutes ago, Ksalway said:

Light came on yet again last night during a snow storm, getting really frustrating as my dealership keeps giving me the same BS response as they can not diagnose if the light is not on , as it does not store a code...

Does the light come on when selecting a different range in the transfer case or when driving around in the same range? My service 4wd light would come on when switching back to 2wd after pulling into the garage. I would back in select 2wd than shift the truck Into park and shut it off. It seems that if you are too quick and shift gears or shut the truck off while the transfer case is still selecting a different range it can sometimes throw a false code. I actually found an article on gmtechlink about this issues. https://gm-techlink.com/?p=11123 

 

Since reading this article I have been mindful to not shift gears or shut the truck off until the transfer case has finished selecting and I havent had any issues yet.  I had mine at the dealership twice for this. The first time I got the light to come on when pulling in. The code read sensor position not plausible. The second time the light went away and they couldnt find any stored codes in the truck. Onstar even said there wasnt any codes in the truck either even though when I called them the service 4wd light and message was on.

 

Edited January 19, 2020 by 19Sierra

[Ksalway]

3 minutes ago, 19Sierra said:

Does the light come on when selecting a different range in the transfer case or when driving around in the same range? My service 4wd light would come on when switching back to 2wd after pulling into the garage. I would back in select 2wd than shift the truck Into park and shut it off. It seems that if you are too quick and shift gears or shut the truck off while the transfer case is still selecting a different range it can sometimes throw a false code. I actually found an article on gmtechlink about this issues. https://gm-techlink.com/?p=11123 

 

Since reading this article I have been mindful to not shift gears or shut the truck off until the transfer case has finished selecting and I havent had any issues yet. 

Nope every time it’s happened is when I’m making a turn in a heavy snow storm(not dry pavement 3-4” on road) and the tires start to spin the traction control and abs go off and then the light comes on. It usually clears itself the next day when I’m back in 2wd. The 4wd still functions even though the dash shows a red symbol... Mostly just irritating I can’t get a resolution for this and get shoulder shrugs when I refer to the dealership. 

[19Sierra]

2 minutes ago, Ksalway said:

Nope every time it’s happened is when I’m making a turn in a heavy snow storm(not dry pavement 3-4” on road) and the tires start to spin the traction control and abs go off and then the light comes on. It usually clears itself the next day when I’m back in 2wd. The 4wd still functions even though the dash shows a red symbol... Mostly just irritating I can’t get a resolution for this and get shoulder shrugs when I refer to the dealership. 

Sounds like your issue is different than mine was. Hope you get it figured out. Next time the light comes on call onstar and see if they can tell you what the code is. Good luck 

[Ksalway]

12 minutes ago, 19Sierra said:

Sounds like your issue is different than mine was. Hope you get it figured out. Next time the light comes on call onstar and see if they can tell you what the code is. Good luck 

Thanks man, I’ll try that

[19Sierra]

Well the service 4wd message just came back on for me again when switching back to 2wd. Truck was moving this time when it did it. Called onstar and they said there are no faults or codes showing. Not sure how as the service 4wd message is displayed on the dash. Guess I get to call the dealer again about it tomorrow.

[Colossus]

It is pretty easy for you to duplicate the issue when you are out there driving in those conditions? 

[Ksalway]

Last snow storm I tried and it didn’t do it it was only a mild storm. The one we had last night was decent and had about 4-5” on the road which caused it to pop on. Started the truck today and the light was off by the time I got to the bottom of the driveway. I’m wondering if it is caused from a fault when the traction control system kick on...

[CNADN SIERRA]

My service 4x4 came on too.  I put the truck in 4x4 for the first time in a snow storm on Saturday.  It engaged fine and it showed 4Hi on the display.  Looked down at my speed a while later and saw the warning.

I tried to put it into AUTO and got a "4x4 transfer in progress" message. But AUTO had an X through it.  Tried 2Hi and 4Hi and some times nothing would happen and sometimes i'd get the  "4x4 transfer in progress" and an X through the 2Hi and 4Hi.  When i got home i restarted the truck and still had the service 4x4.  A few hours later started it again and the message was still there.  Drove it down the road about a kilometer and it went back into AUTO and cleared the service 4x4.

 

This is my first GM truck and I'm not impressed.  The Radio is being replaced on Wednesday cuz it has issues.  Those issues started the moment i got it home from the dealership. Now this.  Ive only had the truck since November.