147 VDC (traction control)

[6x6]

Hi all - first post and it's a plea for help.

I have an 04 plate 147 JTD M-jet... ever since it's been new it's had an intermittent fault where occasionally the screen will flash up "VDC failure" and turn the traction control off - you can't turn it back on with the ESP button. The yellow traction control warning light will come on on the dash.

Turning the car off and on again will reset the fault and then it's usually OK.

When it happens it is ALWAYS within the first 100 yards of starting the car and driving off.

History:
It has been back to the dealer repeatedly, normally they told me they can't definitively fault it unless they see it with the light on, but nonetheless during these visits I had responses including replacing the brake light switch, resetting the system, there's nothing wrong, "communication fault" stored in the memory that they can't do anything about. Each time they fettled it the fault would go away for a few weeks and then return.

Finally a few weeks ago I got it to the dealer with the light on. They said the steering angle sensor was out of alignment, reset it and that should fix it for good. Now it is back with more regularity than ever.

Any ideas what I should be directing them towards??????

[wombat rick]

It's "nearly always" one of the wheel sensors. They don't like the cold and the damp - especially if the car is not garaged - so this is why it happens more at this time of year, especially first thing in the morning.

The other thing which causes it is a weak battery. Again this is exaggerated by the cold weather. OEM Alfa batteries have an indicator on the top of them showing what condition they are in. It should be green. Try checking one morning - before starting the car- what colour the indicator is. If the car does a lot of short journeys with lights, heaters, wipers on it could be the battery is not recovering enough. Also check the battery terminals are clean and the cables are connected tight.

[6x6]

Thanks -

as it happens it does do a lot of short trips and it did seem worse in the recent wet weather. I will check the battery myself.

Chances of getting replacement wheel sensors out of the warranty without a difinitive diagnosis? ha ha.... I should be so lucky!

[6x6]

I checked the battery before using it this morning. Indicator was black. Is that good - the sticker was obscured by the clamp but I could see the options were green, black or white. Then another VDC failure.

Hmmmmm...... it's booked in for another inspection on monday. Time is against us though, warranty runs out in April

Edited by 6x6 on Tuesday 13th February 09:26

[Wombat Rick]

Green means everything is good.

Can't remember the order of the other two.

Give it a run and see if it goes back to green.
Don't think a battery will be covered under third year warranty, but it's worth a go.

[6x6]

Darn thought as much!!!

It was still black by the time I got to work (40 min run) It's weird though - there's never been a problem starting the car, no matter how long it's been left.

Edited by 6x6 on Tuesday 13th February 09:45

[Wombat Rick]

6x6 said:

there's never been a problem starting the car, no matter how long it's been left.

As I understand it it's the momentary dip as you start the car which the sensors don't like. So if the battery is a bit below par, the cold start knocks it down even more and then the sensors have a wobbly. This is why often the sensor warning goes off as soon as you rev the engine and the battery recovers.

Worth pointing out to the garage that the battery isn't going to "green" on it's indicator.

[6x6]

Thanks Rik,

I might mention it, though I don't want them seizing on it as the "obvious" cause, chucking a new battery on it ('specially if I'm paying ) and not doing a proper investigation.... if you see what I mean.