PC Stability control fault

[Flatbiskit]

Hello all, I am having an issue with my PC challenger and am looking to see if anyone here has had something similar as Mitsubishi are running out of ideas.

Apologies straight up as this will be a bit long but there is no way to avoid it to explain what is going on.

When driving normally, or a bit less than that as my son gets motion sickness and driving slow helps, when you turn into a corner the traction control/stability control light on the dash flashes and the ABS goes nuts on the front wheels. It is worse in hilly conditions, and towing seams to make it worse again, such as the clide mountain between canberra and batesmans bay.

Now the thing that is making it harder to diagnose is, it will not do it at round a bouts, sharp corners, normal around town driving etc. It will do it at Highway on ramps and the like but not much more around the city limits. It has done it from the day I picked up the car, but it would only do it once every 6 months and I could not make it do it so I did not worry about it.

Now it is doing it all the time.

Mitsubishi dealer could not get it do it so I took them for a drive and it did it and now they can get it to do it on comand. But with the MUT plugged in all the sensors etc are operating normally and with in spec. They have been in touch with the technical deparment at Mitsubishi and they dont know....

My dealer has deamed the car unsafe to drive at the moment as with each activation of the system it seams to be a bit worse, so I'm with out a car and as any one who is self employed and needs the car for work will know that sux.

So if anyone has any ideas please let me know.

Thanks Geoff

[itsamitsi]

Yep mine does it too zipping around the hills. I believe it to be the suspension lift topping out and lifting a wheel which it thinks is slipping so activates the trac to stabilise the vehicle. It is annoying and has caught my wife out a few times. The only way I can see it getting fixed is remove the lift or lower it 1" which should be enough.

[PeePee]

I get a similar occurance, on windy roads and only on right hand bends, the abs or stability control activates, gives me the shits.

[Flatbiskit]

Hey Itsamitsui and PeePee.

I agree the lift makes it worse, when mine went in (also Ultimate suspension) it was a 3" lift and it was much worse. I called them and they dropped it by about 1.25" and it was much better, back to how it was before the lift.

But the car has been doing it since new and the lift only went in in November last year.

[Flatbiskit]

My dealer has also stated that it is worse when turning to the right which is what I told them.

But evey so often when turning left the rear brakes only will activate.

[old Jack]

1. What are the front and rear ride heights, centre hub to under wheel arch.
2. Do all 4 tyres have similar tread depth?
3. What are front and rear tyre pressures?
4. Does this still happen when the ASC is manually selected "OFF".
5. Has Steering Angle sensor been checked and calibrated?
6. Has Yaw Rate /G Sensorbeen checked and calibrated?

OJ.

[Flatbiskit]

Hi OJ.

See below please

1. What are the front and rear ride heights, centre hub to under wheel arch.
Will have to measure when I get the car back. It is with Mitsubishi. But from memory when it was done they were all very similar.
2. Do all 4 tyres have similar tread depth? Yes they are only 15,000km old .
3. What are front and rear tyre pressures?Running 38PSI all round. I have played with this and it does not seam to make much difference to the traction control coming on.
4. Does this still happen when the ASC is manually selected NO but mitsubishi tell me you cant turn it completly off."OFF".
5. Has Steering Angle sensor been checked and calibrated?Unsure but they have had the MUT connected to the car all day and travelled approx 150km.
6. Has Yaw Rate /G Sensorbeen checked and calibrated?Same for above.

OJ.

[old Jack]

4. Does this still happen when the ASC is manually selected "OFF" NO but mitsubishi tell me you cant turn it completly off."OFF".

Well that is a load of BS and does not inspire confidence in their ability!

The ASTC system is a combination of stability and traction control, there is a button on the lower dash by your right knee, once the engine is running if you push this button then the ASC portion of the system is disabled until you stop and restart the engine of exceed 120kph, there will also be a yellow "ASC OFF" light illuminate on the dash display. By turning the ASC "OFF" you can eliminate the Steering Angle, Yaw Rate and the G Sensors so if the problem continues then it is a Traction Control problem. As others have suggested if your from ride height is too high then you have none or little downward suspension travel so when you corner the wheel can lift off the ground. When this happens the traction control system apples the brake to the lifted wheel and if the ASTC ECU decides it will also cut engine power.

OJ.

[Flatbiskit]

4. Does this still happen when the ASC is manually selected "OFF" NO but mitsubishi tell me you cant turn it completly off."OFF".

Well that is a load of BS and does not inspire confidence in their ability!

The ASTC system is a combination of stability and traction control, there is a button on the lower dash by your right knee, once the engine is running if you push this button then the ASC portion of the system is disabled until you stop and restart the engine of exceed 120kph, there will also be a yellow "ASC OFF" light illuminate on the dash display. By turning the ASC "OFF" you can eliminate the Steering Angle, Yaw Rate and the G Sensors so if the problem continues then it is a Traction Control problem. As others have suggested if your from ride height is too high then you have none or little downward suspension travel so when you corner the wheel can lift off the ground. When this happens the traction control system apples the brake to the lifted wheel and if the ASTC ECU decides it will also cut engine power.

OJ.

Hey OJ

I think I got that mixed up. it is the traction control that is never completly off.

They have not blamed the the lift or any of the other mods to date so finger crossed they keep looking.

I think you are on to the money for the way to diagnose if in ASC or traction control thanks. I will rase it with them on monday.

[old Jack]

Traction Control is turned "OFF" when the Rear Diff Lock is engaged.

OJ.

[Flatbiskit]

Traction Control is turned "OFF" when the Rear Diff Lock is engaged.

OJ.

Well there you go, learnt something today thanks for that. I often wondered that, seamed that way when offroad.

Thanks OJ.

[Ent]

Windy road = Tassie

Heading to St Helens mine with muddies drives me mad. Worst turning on left hand corners. Factory tyres I have not had it cut in on the dry. I think the "squirm" of the muddies triggers it. Important when you have the battery out for a long time the front wheels are straight as I believe the vehicle recalibrates.

Now we are talking normal speed, not pushing it.

Actually St Helens is the worse as even with muddies not a problem on the West Coast. I think maybe St Helen road has less camber?

Anyway, lot of stops to check things before accepted this as an annoying trait of muddies on the East Coast roads.

[PeePee]

1. What are the front and rear ride heights, centre hub to under wheel arch. Will measure later
2. Do all 4 tyres have similar tread depth? All the same and only 12000 k's
3. What are front and rear tyre pressures? I run 38 - 40 but always the same
4. Does this still happen when the ASC is manually selected "OFF". I haven't tried that yet but will next trip
5. Has Steering Angle sensor been checked and calibrated? not to my knowledge
6. Has Yaw Rate /G Sensorbeen checked and calibrated? don't know

When the Ultimate suspension was put in 4 years ago it was not installed incorrectly on the drivers side and the car was higher on the drivers side for some time. I had it checked by the installer 3 times and was advised it was all good. About 18 months ago I had it checked by another installer recommended by Ultimate here in Brisbane, he fixed the incorrect installation (Cost me about $400) however the time it was out has left a permanent position with the drivers side higher at the rear and lower at front passenger side, by about 20 mm. I haven't had time to get back over to the installer on the south side to adjust it to correct it. Eventually I will, I am certain this is the issue for my vehcile.

[Flatbiskit]

Windy road = Tassie

Heading to St Helens mine with muddies drives me mad. Worst turning on left hand corners. Factory tyres I have not had it cut in on the dry. I think the "squirm" of the muddies triggers it. Important when you have the battery out for a long time the front wheels are straight as I believe the vehicle recalibrates.

Now we are talking normal speed, not pushing it.

Actually St Helens is the worse as even with muddies not a problem on the West Coast. I think maybe St Helen road has less camber?

Anyway, lot of stops to check things before accepted this as an annoying trait of muddies on the East Coast roads.

Mine is worse when turning right.....

Yes normal speed maybe even a bit slower as I said my son gets motion sickness so I go a bit slower than normal.

It is very speed dependant, as if you flog the shit out of it through the same set of corners it will NOT do it.

[littleriver]

ours does it even over speed bumps ...

NB jump in vehicle ... start then hit that button to turn off ASC ... problem solved ...



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