1999 E300 3.0 Turbo Diesel ABS ASR Light only when headlights switched on

[mercedesniowner]

Hi,

I'm new to the forum and i'm experiencing a problem whereby I switch my headlights on and I get a dash light ABS ASR. If I switch to full beam the speedo stops working and maybe i'm being paranoid but the steering seemed that bit heavier too. I even noticed this evening that the gear wouldn't change efficiently. Although when the headlights are not in use, none of these issues are present.

I also get a message "Lamp Defective" but all my lights seem to be working fine.

Any help on this matter would be greatly appreciated.

Thanks in advance
Aaron

 

[a111r]

Starting with basics, how good or otherwise is the battery?
With a load applied, measure the internal resistance with a DVM (or use a dedicated battery condition meter).

 

[Ted]

Sounds like an earth issue on the instrument cluster.
Do your dash lights work normally? - i.e. full brightness and dim with the dimmer?

 

[johnsco]

Behind the off-side headlight unit there is an earthing point with about a dozen brown earthing wires going to it.
These earthing points rot like hell and give rise to all the problems you describe.
It is likely that your problem is here.

 

[mercedesniowner]

Folks i think i found the culprit. Behind the o/s headlamp and under the air box there is an earthing point that not only has come unattached from the metal earth point but all the spades are rotten on a 10mm nut that i assume had been welded to metal but this was all surface rust also. Could i trust this to be the issue????? ill leave it to electronic mechanic tomorrow to put new spades on and weld to new earthing point.

 

[johnsco]

Could i trust this to be the issue?????

Undoubtedly !!.
This causes all sorts of problems and is very common on all these W210 cars.
I cured mine by carefully stripping back all the many wires to get to the copper wire, then crimping them to a heavy-duty earth wire which I then insulated.
I then led the earth wire to the studs next to the throttle potentiometer and earthed it there ... away from all corrosion and where I could get at it easily.

 

[toolman1954]

Hi,
What is the rest of the car like for rust ? and more importantly have you checked the front cross member. My old girl never had any such advanced rust as that. I did see a very rusty purple one of these with the front cross member completely rotten in scrap yard.
Be careful if you are going to start any welding around there. Better to follow Johnsco's advice and renew the collective nut and bolt and attach it to a new heavy duty wire or earth braid.
And welcome to the forum !

 

[tim.100]

Behind the off-side headlight unit there is an earthing point with about a dozen brown earthing wires going to it.
These earthing points rot like hell and give rise to all the problems you describe.
It is likely that your problem is here.

Without a forum like this, that car would have possibly ended up costing £100's in labour, or getting scrapped!

 

[johnsco]

What is the rest of the car like for rust ? QUOTE]

Another vital area to check for corrosion is the spring perches at the top of the front springs.
I've has three of these W210 cars.
On one of them I spotted the spring perches starting to fail and got both replaced.
On the E430, one of them actually failed when going over a bump and the spring and associated bits were rolling down the road.
Again - Both were replaced and all is well.
Fortunately - No harm done
This was despite checking them regularly

On a car of this age, where there are some corrosion issues, I would certainly check them 6-monthly - and - whenever you have a front wheel off.

Having said that - These are great cars.
The E300TDs run for ever, and the E430 is great fun.