: StabiliTrak Deactivation for California Smog Test



claymare
12-24-12, 02:47 AM
I own a 2006 STS-V. The California smog test requires a run on the dynamometer at 5 and 50 mph. I deactivated the traction control and StabiliTrak, per the owner's manual, by holding the traction control button for 5 seconds. When the technician attempted to accelerate the vehicle on the dynamometer, the traction control and StabiliTrak would re-engage, preventing the car from accelerating. My dealer could not provide any explanation on what happened, or how to keep the two systems deactivated to perform the smog test. Has anyone had this problem, and if so, how did you resolve the issue to run the test?

carter's_sts
12-24-12, 02:57 AM
We have the same test in my state and there were no problems. I don't think they had to disable either of those, but now that I'm thinking about it, I think they had to move it over to the AWD lane. I asked why and they said because it has traction control.

I didn't get it and didn't bother asking more about it.

boomys10
12-24-12, 02:17 PM
pull the traction control fuse. easiest fix.

Cadillac Cust Svc
12-24-12, 04:39 PM
Claymare, please let me know if you would like me to follow up with your dealership at any point for you! I'm reachable via email at Katie_Lucille@gmexpert.com and will be back in the office after the holidays on 12/26.

I double checked to be sure and your owners manual does state that you should press the TC button located near the shift lever to turn the traction control system off (page 4-10). Pressing the TC button once turns the system off and the traction control system warning light will come on. Pressing the TC button again to turns the system back on. If you press and hold the TC button for five seconds, as you did, the StabiliTrak system and the traction control system should've turned off. Then, pressing the TC button again to turn StabiliTrak back on.

Katie
Cadillac Customer Service

boomys10
12-24-12, 06:54 PM
when dyno'ing mine the fuse had to be pulled. id assume the same for the others that have had dyno done also. just pull the fuse its very easy and will solve the problem, reinstall once test is finished.

FamofV
12-24-12, 08:05 PM
I'm out in CA too and have a 2007 STS-V. When I had it smogged the technician did not deactivate anything. They ran it on a dynamometer and no problems. Is the 2006 V different?

kbf250
12-24-12, 09:25 PM
I also live in Ca. and had mine smogged. The tech didn't have to disable anything.
Also when I turn mine off it stays off until I rengage it. Another easy fix is to unplug
wheel sensors.

1madstsv
12-26-12, 11:19 AM
I pull the abs fuse when I dyno my car. It's the brakes that control the tc/sc so no abs no tc/sc.

TimmyC
12-27-12, 06:16 PM
I pull the abs fuse when I dyno my car. It's the brakes that control the tc/sc so no abs no tc/sc.

This is what I do too. The abs module controls the traction/stability system.

claymare
12-27-12, 07:09 PM
All,

Sorry for my delayed response.

I took all of the input that I received, did some more on-line research, and went back to the local dealer. Their technician did confirm that pulling the Anti-Lock Brake System (ABS) fuse would deactivate the ABS, the Traction Control (TC) system, and the StabiliTrak. He also told me that the car’s on-board computer also monitors and compares all four wheel speeds (on 2wd vehicles as well as 4wd vehicles) , something that, as my other cars are older (’89 Corvette, 97 Silverado), I was not aware of. With that new piece of information, we speculated that, on the dynamometer, the computer sensed a mismatch between the rear wheels running on the dynamometer rollers, and the front wheels which were stationary on the shop floor. Because of this mismatch, the computer then proceeded to reactivate the TC and StabiliTrak after both were disengaged per the owner’s manual (page 4-10) by pressing and holding the TC button for 5 seconds.

I took the car back to the smog check center today, told that technician what was required (pulling the ABS fuse is not a step in his smog check instructions for this car), pulled the fuse, and ran the smog check on the dynamometer successfully at the required speeds of 15 and 25 mph (not 50 mph as I erroneously stated earlier). The technician then told me that they run a no-load smog check for 4wd vehicles (per state instructions) at the required speeds because there are no 4wd dynamometer test rigs (in California, at least). He went on to say that this no-load test may be more appropriate for the car due to the wheel speed sensor comparison check being run by the car’s computer, but the state’s instructions do not include an option to run the alternate test for this car.

Several points for future consideration.

Nowhere in my owner’s manual is there any mention of having to pull the ABS fuse, or do anything else, to pass a smog test under load (i.e., the dynamometer run). California’s instruction to its smog centers is to run 2wd cars on the dynamometer, but 4wd cars can be checked with a simple no-load (no dynamometer) at the required speeds. With that, either,

1) The owner’s (and dealer’s shop) manual needs to be revised to include this step,
2) General Motors needs to informed the states requiring a smog check under load that their technicians need to pull the appropriate fuse(s) to deactivate the necessary systems to run the smog test,
3) GM needs to inform the states to treat their 2wd cars as 4wd cars, due to the wheel speed sensor comparison function being monitored by the car’s computer, or
4) GM needs to provide another way to deactivate the necessary systems to specifically run the smog check on 2wd cars under load, either through the current console-mounted TC button, or automatically when the smog test equipment is connected to the car’s on-board electronics.

I want to thank everyone who contributed to this tread. This is the first time I had posted to this forum and I am pleased for the quick and helpful suggestions that I received, and hope that I can be as helpful to others in the future.

And my car is street legal again!

Cadillac Cust Svc
12-28-12, 02:49 PM
claymare,
We would love to bring this to the attention of the appropriate departments within GM by creating a Service Request. Could we please have you send your findings/suggestion to us either via direct message or email (katei_lucille@gmexpert.com) as well as your name, contact information, the last 8 digits of your VIN and mileage, and the name of your dealership.

All the best,
Sarah (Assisting Katie)
Cadillac Customer Service

YoungBlood_STSV
12-28-12, 04:34 PM
There's another option too, I call it the caveman option. Long press T/C to turn off everything then press the gas and just hold it for about 20 seconds. The car bucks and the brakes grab because of the wheels speed sensors go into a tizzy about the rears spinning and the fronts not. Eventually the computer gives up and the wheels are free to turn.

I wish I thought of "pull the fuse"....surely an easier method.

torched10
12-28-12, 06:05 PM
seems weird that caddy would have this issue--i have other cars with ABS and TC, and id imagine there are lots of those cars in Ca--so are they all failing the testMy other cars are a 2007 vette,a 2010 Shelby and a 2011 EXT--of course my 65 GTO doesnt believe in TC

YoungBlood_STSV
01-07-13, 11:24 AM
seems weird that caddy would have this issue--i have other cars with ABS and TC, and id imagine there are lots of those cars in Ca--so are they all failing the testMy other cars are a 2007 vette,a 2010 Shelby and a 2011 EXT--of course my 65 GTO doesnt believe in TC

If that 65 GTO is in good condition I'll trade all my TC equipped cars for it ;-) Safety first...

claymare
01-16-13, 02:08 AM
Sarah,

I have been away from the forum. I will send Katie the information she requested to the e-mail address that was forwarded.

As for other cars not reporting the issue, it is the combination of StabiliTrak, ABS, and Traction Control that is at the core of the problem. I purchased my STS-V in 2007. 2012 was the first time that the car was required to be smog tested. I suspect that, depending on when StabiliTrak was put into widespread use, more and more cars will soon be approaching the date when they will be required to undergo smog testing.

CMNTMXR57
01-22-13, 01:50 PM
I had to do this to dyno my car. The other option, pull the rear wheel speed sensor plugs (under the car).

I think California is one of the few states still running a dyno (load test), for emissions testing. Most are all OBDII scan, checking for current DTC's, EVAP system performance (the old gas cap test), that all readiniess monitors (I/M system in GM speak), are online, functioning and have run/passed their criteria and not commanding the MIL on, and mileage since last code cleared. So the old IM240 roller test it isn't an issue.

torched10
01-22-13, 02:32 PM
If that 65 GTO is in good condition I'll trade all my TC equipped cars for it ;-) Safety first...
It's a Frame off 4 sped tripiwer vert. Had it for 25 years. Pretty rare to have prof drivetrain. But is be open to offers
et