Service 4WD - Stability System Disabled warning

[2591tdj]

Whenever the outside temperature drops into the 30s or below, I get these alternating dash warnings: Service Four Wheel Drive and Stability System Disabled. They go away when the the temperature is higher. I have not yet had a code reader put on it. Any ideas? 2005 Tahoe Z71

 

[TheFOSS]

Mine's doing the same thing now.. 2007 z71.. had it less than 2 months.

 

[FrankU]

Same here......I just ignore it. It does go away with warmer weather.

 

[F'in-hoe]

I would check the t-case encoder motor.

 

[TheFOSS]

I would check the t-case encoder motor.

Yeah.. from what i've read, that's the problem.. I'll get it checked when i get some more cash! Thanks,

 

[2591tdj]

It's weird

The only time that I would need the 4wd is when I am in wet or sliippery conditions and that's when I get the error messages. Yesterday, it was icy and below freezing and the Tahoe shifted itself into 4wd Low when I cranked it up and would not come out. I tried switching to 2wd stopped, barely moving and in reverse. Finally, after cutting engine off again and again, then pressing the stability button, i heard and felt two loud clunk noises, then it shifted back into 2wd. I tend to think it might be an electrical short since there seems to be a corelation with wet or icy conditions.

Any ideas guys?

 

[FrankU]

I would check the t-case encoder motor.

After your post above . Read the above advise.

 

[BubZX]

After your post above . Read the above advise.

encoder motor is the problem. had a siverado come thru the shop yesterday with the same problem.

 

[F'in-hoe]

encoder motor is the problem. had a siverado come thru the shop yesterday with the same problem.

Now you know and knowing is half the battle. Definitely do your research when buying one of these the price range is crazy. 600 from dealer and found a few online for around 250 same oem part as factory.

 

[2591tdj]

Replaced encoder ring - hope that's it!

I've had no "Service 4WD" messages since last winter. Weather's turning cold and wet and guess what, the error message popped up again. The problem had to be related to wiring or the controller, I thought. So, today I replaced the encoder ring inside the encoder motor. Was a pain lying on the garage floor doing the work, especially with back and neck problems. After I finally found the motor, had to remove the front driveshaft and a small skid plate to get to it.

Ordered the A/C Delco part off Amazon much cheaper than anywhere else. Dismantled the old one and it definitely appeared to be worn out. Couldn't see how the contacts were even working, they were so gunked up. If this doesn't do it, I'll replace the actuator which looks like maybe a 10 minute job.

By the way, the encoder motor is no where near the actuator. The actuator is on the front right of the front dff behind the large skid plate. The encoder motor is part of the transfer case and is at the rear of the front driveshaft behind a small skid palte on the left side. I mention this because I wasted a lot of time trying to find it on the front diff near the actuator and have seen other posters who made the same mistake!