2015 Toyota Fortuner steering and traction issue whilst driving

[Tahirv]

Hi Guys

I desperately need some help or advice,

My dad has a 2015 Toyota Fortuner 3.0 d4d Auto, sometimes whilst driving on the highway he says the steering locks and the traction and vsc light flashes and he has no control of the car and then it switches off and comes back to normal.

This is very scary and I honestly don't know where to start with this issue as it does it randomly and not all the time.

Any Ideas what could be the issue?

[Mud Dog]

I'm not familiar with the Fortuner at all but ir sounds very much like the vehicle is automatically engaging 4x4 (this will make the steering very stiff on a solid surface like tarred road).

To my mind, traction control is something only used when there is a need for it, like on gravel roads and off-road. There must be a switch to turn it off. Do that to avoid the problem until you can get further clarification on whether the unit is faulty or behaving as it should.

Hopefully some of the Fortuner owners can advise further.

[Tahirv]

Thanks for your reply, this model isn't 4x4, just a normal 4x2 fortuner.

I hope so too,

[ROOKIE]

Hi Guys

I desperately need some help or advice,

steering locks and the traction and vsc light flashes and he has no control of the car and then it switches off and comes back to normal.

This is very scary and I honestly don't know where to start with this issue as it does it randomly and not all the time.

Any Ideas what could be the issue?

Hello.

To me, this sounds like the VSC activating. When it does, it brakes individual wheels to try and attempt some stability control. When braking individual front wheels, steering feel will be affected.

I would start by checking all the tyres. They all should have similar wear. If you have recently put a new spare onto a set of well worn types, or for example replaced 2 of the 4, differences in rotational speeds may trigger the VSC.

If all is fine, next check all the wiring to the ABS sensors.

[Tahirv]

I will look into this and get back to you,

Thanks for the reply

[Tahirv]

So it turns out the issue only happens when you are on the highway and taking a bend.(it's only happened like 3 times in about 4 months)

The mechanic says that he thinks the issue is with the angle sensors as there is a difference of 0.4 degrees between them.

Could this be the cause?

[ROOKIE]

So it turns out the issue only happens when you are on the highway and taking a bend.(it's only happened like 3 times in about 4 months)

The mechanic says that he thinks the issue is with the angle sensors as there is a difference of 0.4 degrees between them.

Could this be the cause?

What sensor? VSC uses 4 of them. If he is talking about steering angle sensors, I would be cautious as I think there is only 1 on the steering column. ( I am open to correction on this.. I am merely an interested desk jockey)

See brief write up on VSC attached.

[Bear]

So it turns out the issue only happens when you are on the highway and taking a bend.(it's only happened like 3 times in about 4 months)

The mechanic says that he thinks the issue is with the angle sensors as there is a difference of 0.4 degrees between them.

Could this be the cause?

How’s it.
Don’t have experience with the Fortuner.
In general if it is an electronic fault, even if it is intermittent the computer usually keeps a memory of the faults. Take it to someone with a good diagnostic tool and they should be able to pick up the fault. Taking the mechanics word for what he “thinks” could just end you up in unnecessary costs.

[5thGeer]

Hi Tahirv

Through my experience with working on VSC or traction control systems in general I find that intermittent or sporadic faults are the most challenging to diagnose.

The VSC system relies on information received by a number of sensors.
Generally when there is an electrical fault ie an open circuit or short circuit fault, the control unit is able to identify this and automatically disables the system and displays a warning light. A fault is logged in the control unit and it can be read out at a later time. In case of an electrical fault in the sensor system, the control unit will not intervene, (As is in your case), unless in a case of the control unit being defective.

However there are other types of faults that can occur during certain sensor operating ranges where the control unit receives an incorrect or inaccurate value from the sensor and therefore takes intervention by braking individual wheels or limiting engine torque etc. The control unit does not identify these as faults and therefore will not log a fault code.

A good place to start is by checking all the basics as mentioned by ROOKIE ie Tyre pressure, wheel alignment, suspension for damage, shocks etc.