VSC

[Anthony B]

I and my garage are puzzled by a recurring fault indicator announcing 'Check VSC.'  They have replaced a sensor (I forget what it is called) under the inlet manifold, which has eliminated an engine indicator warning light, but the VSC sign remains on.  Is there an existing thread here covering this problem?  In any event, what is the best thing to look at now?

[Redsteve]

Hello Anthony.

I am not sure whether it is the same on a 430 but on my 400 when one of the ABS sensors failed the VSC light was on all the time. As soon as I replaced the sensor and drove the car over about 20MPH the VSC light went off.

It might be worth a look.

A word of warning though, new sensors are not cheap.

Hope this helps.

 

Steve.

[Anthony B]

Thank you for this suggestion - I'll have my garage look at it on Monday.   I forgot to add that in all other respects the car drives normally, although I haven't had to test it under conditions requiring ABS.  If we get a hard winter ahead I might have to be concerned.

AFB

[Redsteve]

The quick and easy way to check if the ABS and Traction Control (both work from the same sensors) is functioning is to drive onto a piece of grass and give the throttle a quick stab with the VSC function switched on. If you are getting substantial wheel spin then the sensors are not working.

Only one of the four sensors has to fail to shut down the whole system.

 

Steve.

[cruisermark]

HI Anthony

I hope you get yours sorted and if you do please post on here what was the cause - I have had the same problem on my 430 and despite code reading and replacing bank 1 sensor 1 the lights still return with the same error code.

So far I have done the following:

1. Replace Bank 1 Sensor 1
2. Replace fuel filler cap
3. Clean maf sensor
4. Tried a zero point calibration using the paper clip method with no success - Apparently if you used Non -Toyota code reading equipment it causes the lights to come back on therefore a zero point calibration is required.

I must add the car drives absolutely fine - as a last resort I am going to replace the sensor again in the hope that may solve the problem even though the sensor was checked and readings taken and apparently its working fine.

[Anthony B]

Thanks for all the input. I'm not sure what the phrase bank 1 sensor 1 means, but no doubt the garage will know. I am persuaded by the idea that one of my ABS sensors may have failed. Where are these sensors located? At the wheels, presumably. 

AFB

[ColinBarber]

3 hours ago, cruisermark said:

I must add the car drives absolutely fine - as a last resort I am going to replace the sensor again in the hope that may solve the problem even though the sensor was checked and readings taken and apparently its working fine.

Was it replaced with a Toyota or Denso OEM part? Third party sensors don't always work too well.

[ColinBarber]

2 hours ago, Anthony B said:

I am persuaded by the idea that one of my ABS sensors may have failed. Where are these sensors located? At the wheels, presumably. 

Yes, there is a sensor on each wheel hub. However you need to get the error(s) codes read, there are many different faults that will illuminate the VSC light - the codes will help narrow down the problem.

[The-Acre]

2 hours ago, Anthony B said:

Thanks for all the input. I'm not sure what the phrase bank 1 sensor 1 means, but no doubt the garage will know. I am persuaded by the idea that one of my ABS sensors may have failed. Where are these sensors located? At the wheels, presumably. 

AFB

Bank one and two refer to the different sides of the engine, a bank of cylinders on each side of a V8, or V6 etc. And sensor one refers to the oxygen sensor before the catalytic converter, sensor two after the cat, so on a "V" engine you have 4 sensors, two each side.  Any of them not functioning correctly can trigger VSC check. Actually, loads of different faults can trigger it but they are perhaps the most common.

[Boddney]

When one of my ABS sensors failed it put the ABS & VSC Lights together. A new sensor put both lights out.

There was a post on here a (very long) while ago by a fella with the VSC light on, on it’s own and it turned out to be his yare (or is it yor) sensor. If I remember correctly it’s located above the rear axle. 

Bod

[Anthony B]

It's a relief to be able to report that my concern about the VSC and its associated sensors proved to be a kind of false alarm.  It seems that in replacing a sensor which had failed, below the inlet manifold (the fault which had caused the engine warning light to show) the workshop had triggered another when the car Battery was low.  This problem was easy to clear when the diagnostics were analysed.  I'm unclear about the precise cause-effect sequence, but the complexity of the overall electronic system, even with its built-in diagnostic capability, is a reminder of how easy it is for the layman to get lost and to easily believe the worst.

AFB

[Herbie]

On 1/12/2019 at 9:39 PM, The-Acre said:

And sensor one refers to the oxygen sensor before the catalytic converter, sensor two after the cat, so on a "V" engine you have 4 sensors, two each side.  Any of them not functioning correctly can trigger VSC check.

You are correct but it does bring into question what the design engineers were thinking. My understanding is that VSC is Vehicle Stability Control so how on earth does an oxygen sensor in the exhaust bring on the VSC light?

[The-Acre]

2 hours ago, Herbie said:

You are correct but it does bring into question what the design engineers were thinking. My understanding is that VSC is Vehicle Stability Control so how on earth does an oxygen sensor in the exhaust bring on the VSC light?

A question lots of people ask, and certainly one I can't answer! It certainly is strange.

[MLW]

On ‎1‎/‎20‎/‎2019 at 10:01 PM, The-Acre said:

You are correct but it does bring into question what the design engineers were thinking. My understanding is that VSC is Vehicle Stability Control so how on earth does an oxygen sensor in the exhaust bring on the VSC light?

Funny enough I had a front bank 2 oxygen senor fail on of the 4 lamda sensors), and the VSC light came on about 300 miles later. Car was running very well with no symptoms.

When it was replaced the engine management light went off and the VSC light went off. Nervously I waited about 150 miles and switched it on and off, and on and off via the dash button and all worked normally.

The mysteries of a modern car computer!!!

[The-Acre]

1 hour ago, MLW said:

Funny enough I had a front bank 2 oxygen senor fail on of the 4 lamda sensors), and the VSC light came on about 300 miles later. Car was running very well with no symptoms.

When it was replaced the engine management light went off and the VSC light went off. Nervously I waited about 150 miles and switched it on and off, and on and off via the dash button and all worked normally.

The mysteries of a modern car computer!!!

It was a lot easier in the days when you could whip off the cylinder head and grind the valves on the kitchen table to pass a couple of hours on a Saturday!

[Tulpen]

4 minutes ago, The-Acre said:

It was a lot easier in the days when you could whip off the cylinder head and grind the valves on the kitchen table to pass a couple of hours on a Saturday!

And, even though there was a nut and a couple of washers left over...…….the car still ran perfectly.😁

[The-Acre]

5 minutes ago, Tulpen said:

And, even though there was a nut and a couple of washers left over...…….the car still ran perfectly.😁

Yes it did! 

[Anthony B]

I'm glad to say, having launched this thread, that a month later the dash no longer looks like a set of Christmas Tree lights.  And I can switch the VSC on and off at will.  I'm pretty sure that the problem arose from a coincidence of two separate and unconnected incidents, the failure of a VSC inlet manifold valve and a low Battery triggering a false reading somewhere in the ECU.  At all times the car ran perfectly, although had severe weather arrived, with prolonged icing, I wonder whether I would have been able to recover from a wheel lock.  We shall never know.

AFB