Shifting into A4WD all by itself ???

mhraracing · February 28, 2003

Im sure some of you have experienced this same problem that I have.....just driving along in 2 Hi....My 2002 trailblazer shifts into A4WD all by itself....I brought into the dealer last week and they replaced the switch and reprogrammed the computer..but it is still doing it. Not all the time ....but every once in awhile ....this is felt and heard by a clunk....this cant be very good for the drive train. It happened to me yesturday on my way to work on the highway going 75mph.

If this has happened to you...please let me know...and if your dealership has fixed the problem ???

Thanks

HuJass · March 8, 2003

When was the vehicle built?

If you want to get adventurous, go under the vehicle and look at the transfer case. There will be a round metal tag attached to the t-case with a single screw thru the middle of the tag. This will have the build date of the t-case. This would be the starting point in diagnosing your problem.

mhraracing · March 10, 2003

Will do.....I wish I looked at this post earlier....Its dark and cold here now..so....I will take a look tomarrow and give you the build dates....thanks.

D

mcali17 · March 27, 2003

Hey. My dad is a dealer. I did the swap to get my 2002 Envoy SLE. I drove up a 2002 Envoy SLT XL. It did it on the way to the dealer to get my truck. And my truck did it on the way home.

I had the 4 wheel drive control switch p/n 15097405 replaced and the computer reprogrammed and never had the problem again.