Traction control problem (I think)

[dclee]

According to the sales materials I have here, VSC was referred to as Vehicle SKID Control when first introduced. In 2004, that designation was changed to Vehicle STABILITY Control. On the FJ Cruiser it is also referred to in this manner. Not sure whether or not it was recalibrated when they changed the meaning of the acronym.

 

[hoser]

This exact thing happened to me on the old 80 Series. I accidentally busted one ABS sensor when re-inserting an axle shaft after a Birfield job.

Spike, going with Derek's post, right before the first occurence, did she have any work done to the vehicle like brakes, CV shaft, new tires, anything?

 

[-Spike-]

Spike, going with Derek's post, right before the first occurence, did she have any work done to the vehicle like brakes, CV shaft, new tires, anything?

No, but the vehicle was new to her within the past 6 months or so.

-Spike

 

[Atticus]

I didn't mention a warning sound. As far as I know there wasn't one, other than I believe she said she heard something like a motor- but I could be mistaken. It's been a few weeks since she told me about it and my memory sucks.

I can't think of any other explanation for the behavior as it was described to me other than the brakes applying themselves on single wheels, and as far as I know the only system that would be capable of doing that would be traction control. I suppose a blown wheel bearing might exhibit something similar, but she didn't note any odd noises when moving, nor do I believe it would be driveable for several months with a locked-up bearing, with the occasional problem.

-Spike

I'm speculating (sorry), but your comment about her hearing something like a motor makes me think that it has something to do with ABS, and its activation is what she is hearing. Is she sure that the ABS light is not on? It seems very likely that it is brake related, and something is causing the ABS to fire on one wheel, or one side, for some reason.

 

[richg]

I'm speculating (sorry), but your comment about her hearing something like a motor makes me think that it has something to do with ABS, and its activation is what she is hearing. Is she sure that the ABS light is not on? It seems very likely that it is brake related, and something is causing the ABS to fire on one wheel, or one side, for some reason.

That is the VSC, Vehicle Stability Control. It takes wheel speed sensors, steering angle input sensor, acceleration sensors, and driver braking input in order to keep the vehicle on the intended course. It does this by using the ABS equipment as well as engine throttle and timing. Its a very complex system with a variety of sensors involved and certainly sounds like it is the culprit for what is occuring. You pull the ABS fuse though, and you should effectively disable the ability for the VSC (and ABS) to function.

rich

 

[ShottsUZJ100]

That is the VSC, Vehicle Stability Control. It takes wheel speed sensors, steering angle input sensor, acceleration sensors, and driver braking input in order to keep the vehicle on the intended course. It does this by using the ABS equipment as well as engine throttle and timing. Its a very complex system with a variety of sensors involved and certainly sounds like it is the culprit for what is occuring. You pull the ABS fuse though, and you should effectively disable the ability for the VSC (and ABS) to function.

rich

I think we agree, except we cannot figure why VSC is kicking in during regular driving. Tha'ts a puzzler.

 

[Atticus]

I think we agree, except we cannot figure why VSC is kicking in during regular driving. Tha'ts a puzzler.

Grounded wire? Short?

 

[ShottsUZJ100]

Grounded wire? Short?

Doubt it. My guess is mechanical influence.

As I stated before....when my Slee Bump went on along with 863 springs and new shocks I experienced VSC kicking in on sharp turns or moderate curves at high speed and it even cut power. We traced it to a losse DS rear shock my mechanic forgot to tighten. Once tightened it never happened again. Including after adding N74L shocks. Well, he tightened them.

 

[MoJ]

I would definitely pull the ABS fuse until you can get it resolved. There are a variety of sensors involved in the VSC system so hopefully a dealer scan-tool has the ability to monitor them.

rich

Please don't recommend disabling any vehicle safety system without knowing exactly what the root cause is. The vehicle in question should be taken to a dealer for inspection, not be trouble shoot second hand over the internet.

 

[ShottsUZJ100]

Please don't recommend disabling any vehicle safety system without knowing exactly what the problem is. The vehicle in question should be taken to a dealer for inspection, not be trouble shoot second hand over the internet.

Disagree. Driving a disabled 2000+ makes it a 98-99 short only ABS. What Spike reports sounds more dangerous than not having just ABS.

 

[Atticus]

Doubt it. My guess is mechanical influence.

Why? Because of your one experience? Why would that transfer to this situation. Not trying to be hostile; just asking.

 

[ShottsUZJ100]

Why? Because of your one experience? Why would that transfer to this situation. Not trying to be hostile; just asking.

The system works therefore I doubt it is a wire, etc. I believe it's mechanical, something that triggers a sensor/CPU. Like a bad sensor, something in the axle, bad bearing, brake-related......it's my gut and nothing else.

 

[MoJ]

Disagree. Driving a disabled 2000+ makes it a 98-99 short only ABS. What Spike reports sounds more dangerous than not having just ABS.

John -
You, me, and everyone else here cannot be 100% certain of what the root cause is. It may in fact be that the ABS has nothing to do with the cause but is instead the only thing keeping an inexperienced driver on the pavement. Again, diagnosing such a potentially dangerous problem over the internet and then telling someone to disable a safety system is bad advice.
Jason

 

[Atticus]

The system works therefore I doubt it is a wire, etc. I believe it's mechanical, something that triggers a sensor/CPU. Like a bad sensor, something in the axle, bad bearing, brake-related......it's my gut and nothing else.

You are assuming that the system is working to correct the problem. I think it could be causing the problem. Why would a bad sensor be mechanical?

 

[ShottsUZJ100]

John -
You, me, and everyone else here cannot be 100% certain of what the root cause is. It may in fact be that the ABS has nothing to do with the cause but is instead the only thing keeping an inexperienced driver on the pavement. Again, diagnosing such a potentially dangerous problem over the internet and then telling someone to disable a safety system is bad advice.
Jason

I didn't recommend it, though I don't oppose it. Cutting off the system short-term for a ride to the dealer makes sense to me. Little risk. Only ABS is lost. Keep back and drive slow. That's all.

 

[ShottsUZJ100]

You are assuming that the system is working to correct the problem. I think it could be causing the problem. Why would a bad sensor be mechanical?

I'm out.

 

[MoJ]

. Why would a bad sensor be mechanical?

Was kinda wondering the same thing.

 

[Atticus]

I'm out.

Why? Because I don't understand why a sensor would be mechanical? I'm just following up on your comments.

You are impossible.

 

[ShottsUZJ100]

Why? Because I don't understand why a sensor would be mechanical? I'm just following up on your comments.

You are impossible.

I can't define my "gut". I'm no Toyota engineer. We'll see what Spike finds out.

It's like when my VSC/TRAC lights would light by default after I'd lock my CDL. Though the warning lights were lit, everything still worked. They played and played and ended up replacing the $1200 ECU. I told the guy I doubt that would fix it (because everything was working). It still did it (malfunctioned). After more reseach they replaced a faulty CDL switch in the T-case for $5.00. Problem solved. Toyota ate the CPU and bought the switch.

 

[Atticus]

I can't define my "gut". I'm no Toyota engineer. We'll see what Spike finds out.

It's like when my VSC/TRAC lights would light by default after I'd lock my CDL. Though the warning lights were lit, everything still worked. They played and played and ended up replacing the $1200 ECU. I told the guy I doubt that would fix it (because everything was working). It still did it (malfunctioned). After more reseach they replaced a faulty CDL switch in the T-case for $5.00. Problem solved. Toyota ate the CPU and bought the switch.

That's reasonable.