TCS turns off when it's supposed to activate
 

So for a month now, my TCS turns on and off just fine with the switch, but when I give it some real gas and spin the tires a bit, the TCS off light comes on and it doesn't prevent the spin anymore. Restarting the car resets it, but it does the same thing the next time. I couldn't find this exact issue with a search. Any ideas?

I would scan the ABS system and see if it has any error codes stored in it. The TCS could be shutting down on you if you have a sensor problem, etc.

If you can get in to one safely, you may also see if you can activate the ABS system. If you have a bad sensor, it will cause a problem for both the TCS and ABS. (I would expect you to get an error light on the dash if it doesn't like what happens in an ABS situation.)

I've had to slam on the brakes for lights a few times while this problem has been happening and the abs seemed to work fine, haven't had an abs light.

I only have access to a regular code scanner and the only codes are o2 sensor related which I already knew about. I don't have access to any other scanners. It's going to be in the shop this week for something unrelated and I was going to have them diagnose it if it wasn't something simple. I'm think it's just a bad tcs module but i'll let them figure it out.

You'd need to be in a situation where the wheels would slip deferentially in order to really exercise the ABS, like skidding the car on icy or wet pavement. When the ABS activates, you'll get the LOW TRAC light on the dash. If there is an error, you should get an ABS INOP or BRAKE warning light also.


Hopefully they can poll the ABS/TCS codes for you. "Diagnosing" is something else, but having knowledge of any codes will be helpful to all.

I recall the ABS and TCS "module" are one-in-the-same. (I ordered my car without it because it only works for slips at slow speeds on our cars.) So, I'd expect a problem with the module or system's physical valves would also manifest issues with ABS performance.

Speaking of speed... What does your speedometer say when you slip the tires and the TCS shuts down on you?

Reviving this thread to let you all know I found the issue, even when the shop couldn't.

I bought an absolutely amazing bluetooth OBDII adapter. I already had a Scantool MX bluetooth adapter, and that works well with torque, but this thing... man, what a steal. It's called "bluedriver" I doubt any of our sponsors sell it but in case they do I'll just give you the name to search and let you know that it's $99 on amazon.

Anyway, it connects to your phone and can read ABS/TCS codes for our vehicles and many, many others. To my knowledge it's the only bluetooth adapter that can, and the next cheapest solution for reading ABS/TCS codes at home is about $250.

It found the codes in the BCM history immediately, and it turned out i had an intermittent low signal from my TPS sensor causing the issue. Replacing the sensor fixed that issue, and another issue I was having that didn't have an associated code.

Really great tool, I highly recommend it.

Got excited about this. I have 1998 with the TCL light on. But after looking at the web site they don't scan the ABS module. Dam one year wonder that my car is.

thanks for updating , its always nice to hear the outcome when the issue is fixed.