Trio of warnings & no steering?

[Lewisp12]

Hello guys, just wondering if any of you have experienced this or know anything about it:

This morning my wife was driving her 2007 A Class, when these beauties popped up;





Suddenly, there was no steering and the car refused to move. After restarting the car, it was ok again, but now this keeps on happening...
Upon the car being checked by the AA man, it turns out there is nothing mechanically wrong with the car. Fluids are good, brakes are fine... all is apparently well. Could this be a faulty sensor? Or multiple sensors, ABS perhaps?

And, is it strictly a job for the posh chaps at a main dealer, or can anyone tackle it? (I'm in the Heathrow Airport area)...

Many thanks!

Edited by Lewisp12 on Monday 10th June 14:53

[StephenP]

Knackered battery? I seem to recall seeing similar random errors on a car with a battery that was nearing end of life.

Could be wrong though!

Edited by StephenP on Monday 10th June 15:11

[richarda0109]

Battery was my first thought as well.

Rgds
Richard

[HarryW]

If the battery proves good this sort of thing can come from having a noisy voltage. In the case of old 5 series it is ignition barrel main contractors arcing and throwing random complex faults.

[Lewisp12]

Thanks for your replies guys.
I also thought about the battery - I bought and installed a Bosch one.

For a short while everything seemed well, until it happened again...
The symptoms are as follows;

1) The same 3 messages appear on the display unit (as above on pics),
2) The steering goes heavy, (feels like power steering goes).
3) It doesn't accelerate past 2500rpm or so, and it only does 72mph...
4) Speedo and fuel gauge do not function, but the rev counter does.

Any ideas?! Many thanks!

[HarryW]

As I said before there is noise or a power interruption that is logging these faults, don't know if ignition switch is an issue with A classes.
To reset logged faults in this area on Mercs is to turn the steering fully from one lock to the other, if it clears then they are not full falts just logged transients. whenIf it comes back again and you clear it again then you definitely have intermittent power interruption.
The not going above 2k5rpm is a safety feature to limit your speed whilst you have major fault codes so is a symptom.

Let us know how you get on.

[HarryW]

Ok had a quick goggle for you, it seems that a faulty (intermittent) brake peddle light switch can give some if not all of your symptoms, £10 switch got to be worth a try.

[Lewisp12]

Thank you HarryW. I will try the lock to lock steering and see what happens.
I too, have read lots of threads related to this problem.
It turns out it can be batteries, alternators, brake switches, ignition barrels, etc...
I guess the thing to do is plug it in.

I will keep you guys updated.
Many thanks!

[HarryW]

To add to that list, particularly as you had a power steering 'fault' at the begining is that a front wheel sensor can induce it. Apparntly if the fault comes on when you go to full lock it could be the front sensor or associated wiring.

I suppose it's would be best to try and replicate the fault symptoms methodically to understand where the fault oringates rather than changing everything one at a time.

In the past I've had a 5 series ignition barrel arcing contacts that threw spurious faults and a on a TT a brake light switch that gave lots of ABS/ESP type faults.

I suspect there is one fault, statistically it is unlikely to be more i.e. the root cause.

[jith]

I think that instead of all this guess work and buying parts you might not need, you should have a proper diagnostic check done and see what codes come up.

I had an S class in that was dangerous to drive as it tried to pull the steering out of your hand! It flagged up no less than 13 fault codes related to the ABS and traction control systems.

All it needed was one front ABS sensor. The Mercedes system of programming is seriously flawed.

J