LEAVINU

Hello all,

So my C6 doesnt have TPMS installed and 1 out of 10 times I can luck out and get the car into comp mode. Why is this?

What are my options in order to get comp mode engaged when I want it?

rag1998

I run my car without TPMS @ track, my street wheels do have TPMS.

When I switch from street to track wheels, I run the car on street for about 20 mins until the TPMS service light comes ON & the tire pressures on your DIC should read XX XX, keep running the car for about 5 mins after this & you should be able to select whatever mode you want to...

Hope it makes sense..

BTW I ran COMP mode on track without TPMS 2 weeks ago & had no problems will be running with all the controls OFF, without TPMS next weekend..

davidfarmer

just the way it is....if you want AH/TC, you need TPMS. If you keep your street wheels out, and park with them around the car, you might trick it enough to keep the computer happy, but once it decides the system has failed, you are out of luck (at least in my 06)

I simply run with AH/TC shut completely off.

rag1998

Thats weird mine is a 08 & that isn't the case with mine, ran mine in comp mode without TPMS no problems at all even AH kicked in a couple of times on the track

LEAVINU

Two different experiences posted above so far. It seems w/o the TPMS it will only run TC on or off. Its like hitting the lottery to get comp mode to engage.

So the TPMS are a part of the comp mode setting? Meaning, no TPMS means no comp mode?

If only TC on or off is the option than what is the status of AH at that time? Comp mode to my understanding kills TC but leaves AH at 50% for the just in case factor.

Dr.Ron

Here's a 3rd story for you.

My 1st time out on Hoosiers mounted up to wheels WITH TPMS installed was a month ago. I didn't have the reset tool. I figured it wouldn't be a problem, as I drag race w/ drag radials with NO sensors installed and NEVER have had a problem on 2 cars (06 & now 09Z's) in 4 years.

1st session- NO PROBLEMS.
2nd session-tire pressure light on & can't get comp mode. 1st lap, 1st turn at 45mph AH starts applying the brakes to 1 wheel. Loud noise coming from that wheel. I couldn't get ANY speed on ANY turn as the brakes kept getting applied. Pitted in, shut down, go back out=same thing. Disconnected the battery, reconnected & tried again=same result.
Found someone w/ the TPMS reset tool (Thanks 95Jersey!), and I never had another issue for the rest of the day.
Needless to say that night I ordered the tool from Tire Rack. That was awful AND I lost an entire session from it.

Once the computer realizes there's a problem, it thinks you have 4 flats & is trying to prevent an accident...

Ron

davidfarmer

whatever happens, it usually gets worse as an event goes on. We've had events where nothing happened, but we've had events where the car was virtually undrivable (at speed) without shutting the system completely off.

as Ron says, it is simply a matter of the car going into safety mode.....it assumes you have a flat tire (or 4), and does everything it can to prevent your having an accident.

gkmccready

I had a bad sensor once and even with everything off the car noticed one tire randomly claiming 0psi... it slammed on the brakes entering T10 at Thunderhill and I was *VERY* lucky to have established enough gap from the car I just passed not to have him occupying my hatch.

That said, I still have TPMS in all my wheels...

varkwso

that has been my experience with C6s also. It often will not even let you turn the AH/TC off and it goes to a very safe mode.

jvp

I've had a considerably different experience with my two 2007s at the track, sans TPMS. They both reacted differently, though, which was strange. Almost like there was a mid-year AHS computer change.

Bear in mind, the road course I go to is about 45-50 miles from my house. My standard operating procedure is to change the wheels/tires the night before the track event and drive to the track on them since it's so close. Twenty or 25 miles into the trip, the TPMS computer on both cars would complain: "Service TPMS".

At the track, they responded a little differently.

Car 1: start the car, wait for the "Service TPMS" error, clear it, put the car in any mode I want (usually Comp mode).

Car 2: start the car, wait for the "Service TPMS" error, clear it, stall the car. Start the car immediately back up, wait for the "Service TPMS" error, clear it, put the car in any mode I want (usually Comp mode).

You need 20-25 miles driven between the time you remove the TPM sensors and when the car realizes they're actually gone. Once it realizes they're gone, it'll error immediately when the car is started. Once it errors, you should be able to put it in any mode you want.

jas

LEAVINU

So in short until I get TPMS in each wheel I'm screwed.

When I hit the TC button the DIC reads "Traction Control System - OFF." This means AH is still on correct?

dvandentop

this was shown on a episode of vette garage when pfadt was racing what a biatch the tpms can be.

jvp

Yep. If you hit it again immediately, what happens? Does it go into Comp Mode or does it return to "All On"?

What happens if you start the car, stall it immediately, then start it back up? I know that's friggen weird, and I never really figured out WHY that works that way, but give it a shot. In fact, you don't actually have to start it the first time, just power the electronics up, let the TPMS error pop up, then turn the car off. Start it immediately after that and, after clearing the TPMS message, try working the TCS button.

jas

LEAVINU

Here is what happens:

• Start the car
• "Service Tire Monitor" appears
• Hit reset button to clear
• Press TC button once
• "TC Off" message appears
• Press TC button again
• "TC On" appears

You know whats funny is that there have been a few times I tried to start the car and it didnt fire the first time (cam, not pressing the start button just right). I'm wondering if those are the times it did go into Comp mode. That rarely every happens so its hard for me to recall.

I'll definitely give your suggestion a try tomorrow and report back.

rbl

Yep ... Unless you put them in a piece of 4" and 10" PVC with a valve stem and 32 PSI neatly stuck in the back and forgotten about forever.

LEAVINU

Thanks all. I have an email out to Gene for a set. Wonder if they will fit the c5z wheels as well? I'm looking for a set of those but hopefully all 18's. LMK if you know anyone willing to part with 2 or 4. Will be track wheels but really don't want some all beat up.

Z06_505

Here's how I did it...old water filter canister (already a pressure vessel) and a piece of aluminum with 4 holes to mount the tpms and to keep them from jostling around and breaking. I made plate just long enough to fit in cartridge vertically. Plugged the outlet and put schraeder valve in inlet and painted to match tub. Mounted it in storage box in rear. Done with TPM woes forever.

Me2d

+1 to this solution, but it is a "little bit" illegal in the States - and tabuized isn't it?

fatbillybob

The X-water filter is pure genius!

All you guys running with active tpms sounds dangerous on track. That one guy who had the system active at the wrong time could have spun you into a cement wall. We need a way to turn the system off with HPTuners or EFI live. Can that be done?

Cap'n Pete

I thought that to turn everything OFF you have to press and HOLD the button for 10 seconds? Have you tried that?

I just picked up a 2010 C6, and plan to put a set of wheels on for the track. I'd rather save the $$ and not have to buy another set of TPM sensors, but I don't want to have the car run in "limp mode" either .

So all you guys who are saying you're running successfully with all the nannies off, do you get the error message on start up, then press and HOLD the TC/AH button, and the system shuts off, or do some of you still have the system "active" (or it refuses to shut off, even holding the button for 10 seconds??).

Very confusing/frustrating issue, and weird that not all cars are alike?!