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MG MGF Technical - power steering failure

The power steering failed on the F last weekend in the middle of an autotest - made that wiggle woggle very difficult and steering incredibly heavy.

Problem solved (hopefully permanently) by cleaning all electrical contacts and fuse. But surely it can't be that simple?? Is there another likely cause.
David
david stonehouse

I have removed the EPAS fuse on my F.

That's why I couldn't believe this statement "made that wiggle woggle very difficult and steering incredibly heavy."

Without EPAS the steering is terrific and no heavier than a warpainted French shopping trolley that I used to own. You can really fling it about without EPAS.

Get yourself to a gymnasium, you weedy boy.
Amos Brierley

thay ent got no jimnazeeums here, silly bouy. I gits me strenth from liftin me point of bere here in the Woolpack.
Hay, I fault you were ded Amos?
Emma Dale

And to actually answer your question! there is a rotor connector in the steering column, occasionally this gets dirty/worn MGR will replace it rather than clean it. When the ECU identifies a strange signal in the system it will shut itself down, disengaging the electric cluch and leaving you with standard steering, it will NOT impair the steering at all.
When the ignition is switch off and back on again the EPAS rechecks the circuit, finding nothing wrong it will continue to operate untill it picks up the fault again, so you may not have fixed the fault. The EPAS ECU keeps a history of fault codes which can be sucked out by the testbood whilst the dealer sucks money out of your wallet.

Will
Will Munns

Just a slight correction on Wills excellent posting the failure does not leave you with standard steering - it leaves you with no power assistance to the steering. STANDARD non-power assistance has a different ratio to the STANDARD power assisted steering.

Ted
Ted Newman

O.K, I thought that and thought it might muddy the response, the important point is that it leaves you with direct drive to the wheels, rather than a direct drive with a huge extra weight like some power steering systems do.
The car is _not dangerous to drive_ with the EPAS disabled
Will Munns

"there is a rotor connector in the steering column"

Is this the same rotary coupler that screws up the SRS system?

If so, then the SRS light should come on at the same time as the EPS fails and vice-versa

Brian

Brian

No this is a different one - the PAS one is a torque sensor on the column itself which basically reads how much 'effort' you are putting into turning the wheel and then decides if you need assistance - and it was generally agreed some years ago that this is what can cause (or at least partially cause) the feeling of 'twitchyness' when you perhaps abruptly correct a slight deviation whilst travelling at speed on a straight road and so cause the torque sensor to be activated.

Ted
Ted Newman

So there are two things to go wrong in the steering wheel. I was looking for a clue to occasional SRS failure.

The variable effort certainly makes dodging an obstacle at high speed a bit hairy. The car definitely swerves very energetically.
Brian

Brian

The biggest problem is not in the steering wheel - its behind it:-)

Ted
Ted Newman

Brian,
The EPAS torque sensor is not actually a rotary coupler as for the airbag and it is not in the steering wheel!
It is located about half way down the steering column and is a sort of spring loaded arm which moves with the movement of a sliding collar on the shaft! As the torque increases so the collar moves along the shaft and the spring loaded arm is moved, sending a signal back to the EPAS brain.
Jason H
Jason H

ITS THE BIG NUT LOOSE BEHIND THE WHEEL
jor

Thanks guys
Maybe it is the big nut behind the steering wheel thats the problem!!!!!

I found the driving on the road a little heavy but Ok. However, autotesting (as demonstrated by Russ Swift at Silverstone in the past) requires a responsive wheel, opposite lock, some welly and a good handbrake. impossible with EPAS failure but gives the others a chance to catch up.

If interested in Autotesting come to Gt. Massingham airfield on Sunday, 14th July - very nr Kings Lynn, Norfolk.
David
david stonehouse

If you do it like Russ Swift the steering should be light - he onlys has one wheel steering!

Ted
Ted Newman

This thread was discussed between 28/06/2002 and 05/07/2002

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