2006 Trailblazer LS steering position/angle sensor
 

I've got a 2006 Chevy Trailblazer LS, with the 4.2l in-line 6 motor.

I got this vehicle about 6-7 years ago and when I got it the dual warning lights were on, indicating the steering angle/position
sensor was out (most likely).

I replaced it with a Dorman brand sensor. Some of the Youtube video's and guides showed this as being a pretty difficult job
but honestly, it wasn't that bad.

This worked, the warning lights were off after the reset, problem solved. Fast forward to last year. Same problem. So I did the
same thing again, but honestly I messed up. I had secured the steering wheel but I accidentally moved it. I went through with
the replacement anyway and it worked for about 3-4 days then the warning light came back on. I just assumed that this was my
fault.

About 2 weeks ago I finally got around to replacing it again. I went with Dorman again because it lasted about 5+ years the first
time and I sincerely believe that the second one was my fault due to moving the steering wheel. I made absolutely sure I didn't
move the steering wheel this time (duct tape, for the win!).

Unfortunately, it only lasted about 2 weeks and the light came on today. On a straight stretch, at about 35-40mph. As soon as
I got home I turned it off and back on again a couple of times and it didn't come back on but I can only assume that, like before
it's going to get worse.

So my question is, since I am 100% sure I installed it correctly this time, what else could it be or is there something that is causing
the sensor's to go bad prematurely?

Thanks all.

What is/are the trouble codes being set?

Is the alignment good and the steering wheel centered when driving straight?

I've not gotten the codes yet. Next time I'm out to town I'll see if any are there (history) since it only did it that one time
after this install.

I had a front end alignment done last year after I put in new outer tie-rod ends and CVS (wheel bearing) units. As far
as I know, it's okay. It seems centered when I'm driving on a straight stretch of 4-lane road.

Can that cause the 2 warning lights on the dash to come on?

Thanks.

Depends on what the sensor is actually reading when it’s being driven straight. If it’s near zero degrees then probably not - if it’s offset to the left or right by more than 5 degrees then it could be.

Which warning indicators were you getting?

These two:


https://cimg2.ibsrv.net/gimg/chevrol...6887515a9.jpeg

The one on the left is “Service Stabilitrak” - the one on the right is the Stabilitrak indicator which comes on only when the system is active, manually switched off, or disabled due to a fault (see page 3-41 of the owners manual for more detail).

The SWPS is a very common cause of stabilitrak problems but there are several other possible causes as well, especially on a vehicle that’s 18 years old.

I’d recommend getting the codes pulled by a shop with a factory equivalent scan tool (or a dealer if need be). Parts houses can typically only pull codes from primary modules (PCM/ABS/Airbags) which may not have any useful codes stored.

The Stabilitrak system is controlled by the ABS module, but the steering wheel position sensor is a “smart sensor” meaning it’s both a sensor and a module in one assembly. IIRC, you actually have to build the vehicle as a 2007 with the scan tool in order to read data/codes from the SWPS.

I'll be going out today so I'll stop by at a couple of places and see if they can retrieve any codes and report them back here.

Thanks. :)

Well, things continue to be interesting...and mysterious. No easily solvable solutions here. :)

I stopped by O'Relly's, Advance Auto Parts, and Auto Zone to check for codes after the warning lights came on. This all took a while because I had
to wait until it flashed on. It still just comes on at random times and sometimes not at all.

The thing is, they detected no codes whatsoever - completely clear. Nothing in history either.

I was told by the workers at these places to wait until it came on, then bring it by without turning the motor off so they could check it. Well, I did that
and guess what? With the warning lights active on the dash, and the motor running, still none of the places above could get a code. Completely clear.

So...besides the steering angle/position sensor, what else could be causing the warning lights to come on?

Thanks <pretty baffled in Kentucky>...

Like I stated before - parts houses usually only check codes in the primary modules, meaning they have the most direct involvement with vehicle systems - 3 or 4 modules at most.

Off the top of my head, I can think of at least 10 modules that your trailblazer will have - many of which aren’t accessible by basic, handheld scanners.

So, did any of the parts houses do a complete system scan? Meaning, checking for codes in every single module on the vehicle?

If the whole system is truly code free (which I find difficult to believe given my experience with GM vehicles of this era) then the problem is occurring at a time when the criteria for setting a code isn’t being met (unlikely given the indicator lights and warning messages) or the instrument cluster is malfunctioning.

The list of possible causes is quite long (wiring and connections being the most likely cause if it’s not component related), but one way you could verify if it’s a SWPS issue again is to make a couple of U turns in both directions. If the lights come on again during or after a U turn, the SWPS and related wiring are suspect.

Okay, sorry to take so long to get back to this, lots of other things going on - life, the universe and everything. :)

Anyway, I can do u-turns and sometimes the SWPS warning light will come on and sometimes not - mostly not.

I can drive 15-20 miles and it never come on. I can start the vehicle in the driveway and have it come on at
start up, other times not. I can be driving out of Spurlock Creek (where I live), about 3.5 miles, all curvy, some of
them very curvy and it not go off - then be doing 60mph down the 4-lane (straight) and have it go off.

I've not managed to schedule a full computer test yet, but it's on my list to see if they can find some code or the
other because the simple scanning done at the auto parts stores here is not picking anything up.

Thanks.