View Full Version : Switching to 4WD drive uncommaned!
OURREDJEWEL
04-29-2007, 12:48 AM
I have an 02 Trailblazer which has been switching to 4HI without me selecting it. The way I notice it is when I turn I can feel the front wheels grabbing, I will look down at the switch and it will flashing in 4HI. I can cycle the switch and it comes out fine however, tonight when I cycled the switch I went to 4LO (while it was in park) it lunged forward about a foot or two but still went back to 2WD after selecting 2WD. Any help would be appreciated.
pogbobo
04-29-2007, 01:28 AM
welcome to the site! I think that is a known problem on some years, something about a faulty switch... there might be a TSB on the issue and I'm sure someone who knows for sure will chime in :)
also, have you tried getting any diagnostic codes? advanced auto can do it for free I think ...
in the mean time, you can see if this link works. its a pdf document of all the TSB's for your year.
http://www.trailvoy.com/docs/tsbs/2002TB-TSB.pdf
good luck! -Matt
PROSPHOTO
04-29-2007, 10:50 AM
There is a bulletin addressing this concern that looks at the transfer case motor/encoder that is on the transfer case. If DTC C0327 is stored, the sensor is malfunctioning and will need to be replaced:yes:
Upon replacement, you will need the dealer to reprogram the transfer case control module with updated software :yes:
OURREDJEWEL
04-29-2007, 11:39 AM
Are the TSB's for info or is there any manufacturers obligation? I don't have a maintenance manual yet, can you retrieve the codes yourself without any special equipment?
PROSPHOTO
04-29-2007, 07:30 PM
The TSB's are for information/there to assist a Technician when diagnosing a known common failure/problem. GM is not obligated to repair the vehicle once it's out of the warranty.
You will Not be able to retrieve the code(s) without a scanner :no:
A generic OBDII code reader may not be capable of retrieving the "C" codes, as they are not emission related; which is why your check engine light will not come on with this failure http://www.unixboard.de/vb3/images/smilies/sm-nachdenk.gif
You may need a more advanced scanner than advanced auto or auto zone use to pull this code