2004 quad. had the soft ware updated hoping to fix problem, still will not show a code when service 4wheel steer light comes on. qs will only shut off at hwy speeds i can drive for weeks under 40mph and never have a problem. used a dealers tech 2 to read codes. dealer told me that he THINKS it is the rear wheel position sensor. i also have a ground problem with my trailer lights, dose the QS and trailer lights ground in the same place?
if you have any ideas that i can try at home before i pay the dealer for something that he thinks is wrong.
thanks again.

Hi there,

I don't think many people check this forum nowadays, but you could do a search and possibly find something or check other GM forums. I am not sure what the problem would be that your having sorry.

thanks. this site looked like it was a good place to find help. did the western tune help? i wish i could find a tech 2 to use over the weekend so that i could capture live data that will not store codes in the computer. well the best of luck to all of you that still look at and use this site for your research.

I am having a pinging issue with the westers tune, so I am going back to stock I just found out that Bully Dog makes a module that flashes our computers and has 3 different setting for power, so might try that. Yea having a tech 2 sure would be nice. Hope you can get it figured out..

well the problem has been found. the reason that i am responding on a web site that is not used is because this place is a great place to do research. i had read on past posts about a ground problem at the qs computer at the rear of the truck. well i dropped my spare tire and found that my two ground wires were GREEN. i cleaned up the contacts and sprayed the ground wires with WD-40 and did a very long test drive to test the results. problem fixed. this might be something that all of us qs owners might want to think about. spray some type of sealant on your ground wires before and after winter. one last thing i need to say. DC current runs on the out side of the wire and a AC current runs in side the wire.this is why automotive wire is braided wire. and a open ground at the back of the truck is just asking for problems because the wire corrodes from the out side in.

Glad to hear you got it fixed! I am going to check mine also now...thanks for posting this.

Hi new guy,Welcome to the site.just read your post about the ground problem. want to add a couple of things.I think that dc current runs throught the wire & ac current(the higher the frequency)runs on the outside.also you might want to check the crimp on the terminal & replace it, if it looks bad.there is really no way to check if corrosion got between the wire & crimp.if you replace it, maybe put some anti-oxident on the wire & terminal 1st before crimping it. thanks for writing in about this,because I want to check mine to see if it's alright,and fix it up before a problem can occur.