traction control glitch?

[Chayton]

today I was driving on the freeway at about 60 mph when I noticed the TC light started flashing, distracted by the light I didnt notice traffic suddenly started slowing down, While the light was blinking I mashed the brakes, and they did not work very well at all. I just read something about TC using ABS sensors (info from crownvic.net) is this why the abs did not really work at all? Im assuming that the ABS sensors may be dirty, and thats why that happened. After the TC light went off I tested the brakes and they seemed to work fine...

[JoeBoomz]

Are you running non-stock tire sizes?

[Chayton]

oops. forgot to clarify, this panther(and my only panther) is a 98 police interceptor. Probably should get around to making a signature...sorry

[RF Overlord]

I mashed the brakes, and they did not work very well at all. I just read something about TC using ABS sensors (info from crownvic.net) is this why the abs did not really work at all?.Describe "not very well at all". When ABS malfunctions, it defaults to a "no operation" condition, meaning the brakes act just as they would if they were non-ABS. It shouldn't affect the basic operation, you just won't have the rapid modulation that ABS provides.

Yes, TC uses the rear wheel-speed sensors to detect excessive slip, but if you had a WS sensor issue, you should have gotten an ABS code.

[Chayton]

Describe "not very well at all". When ABS malfunctions, it defaults to a "no operation" condition, meaning the brakes act just as they would if they were non-ABS. It shouldn't affect the basic operation, you just won't have the rapid modulation that ABS provides.

Yes, TC uses the rear wheel-speed sensors to detect excessive slip, but if you had a WS sensor issue, you should have gotten an ABS code.

the brakes did engage, but it felt like the back wheels were locking up and the car was sliding

[Mebot]

Subscribing to this forum since this is exactly what happened to dad's blue. It happened coming back from Kentucky this past April. And again a couple weeks ago en route to a CAM meet up.

sent from a Samsung Galaxy far far away...

[RF Overlord]

the brakes did engage, but it felt like the back wheels were locking up and the car was slidingYup, that sounds just like the ABS was not functioning. Are you sure it was just the TC light and not the ABS light, too?

[Chayton]

Yup, that sounds just like the ABS was not functioning. Are you sure it was just the TC light and not the ABS light, too?

well it was weird, after I accelerated, the TC light caught my eye, I kinda stared at it waiting for it to go away, looked up and saw traffic coming to a halt, so I slammed on the brakes, which locked up.. dont recall ABS light coming on. I pulled over because I thought maybe I had a flat or something, but everything was ok. Afterwards they worked fine.. strange:confused: Will ABS not function when traction control is engaging?

[RF Overlord]

Traction control is a function of the ABS system, but operates in opposite fashion. Where ABS detects a wheel that is turning more slowly or stopped and modulates the brakes to prevent the wheel from locking up, TC does the opposite. When it detects a wheel on the rear axle spinning faster than the other one, or both rear wheels spinning faster than the fronts, it applies the brakes to slow the spinning wheel(s) down.

I'm not sure it's possible to have both TC and ABS active at the same time...

[EMAS]

I'm not sure it's possible to have both TC and ABS active at the same time...

Correct if the computer gets a signal from the brake switch it won't activate the TC. I also believe if it detects a malfunction that causes the TC to shut down and flash the TC light then the ABS is shut down as well.

[frdwrnch]

You have an issue with one of the rear ABS sensors. Look for metal filings on the sensor, rust or any other debris on the toothed rings. This may not code as the ABS module truly believes one rear wheel is not moving at the same speed as the other.

[RF Overlord]

This may not code as the ABS module truly believes one rear wheel is not moving at the same speed as the other.I wondered about that...Mary's car had a weird issue with the LR sensor and it didn't set a hard code until it broke off. I guess if the output is there but corrupted in some way, it reacts differently than when the output is completely missing. Thanks EMAS and frdwrnch for clarifying...

[Chayton]

You have an issue with one of the rear ABS sensors. Look for metal filings on the sensor, rust or any other debris on the toothed rings. This may not code as the ABS module truly believes one rear wheel is not moving at the same speed as the other.

update: frdwrnch is correct. The other day my TC problems got worse, I could not even move the car without the traction control completely engaging, it was cutting all engine power and the vehicle would barely move. I took the rear rotors off and the sensors were covered with brake dust and gunk, probably 15 years worth. I cleaned it all down and installed new pads, and that solved the problem. If you are having abs/TC issues, clean those sensors!

[Mebot]

update: frdwrnch is correct. The other day my TC problems got worse, I could not even move the car without the traction control completely engaging, it was cutting all engine power and the vehicle would barely move. I took the rear rotors off and the sensors were covered with brake dust and gunk, probably 15 years worth. I cleaned it all down and installed new pads, and that solved the problem. If you are having abs/TC issues, clean those sensors!

Word. Will do

sent from a Samsung Galaxy far far away...