Number Plate Flashing

[Barachello]

The other day I received an indication on the dash display that one of my number plate bulbs (left side) was defective.

I have tried changing the left bulb, with no change. So I changed the right one as well, after cleaning both contacts, in both sides.

I then checked the wiring going to the left bulb and tracked it back to the rear sam. Disconnected, cleaned and reconnected all connections.

Still no joy.

THe left side bulb is flashing every couple of seconds.

Has anyone else had the same problem, and found a solution ?

(I have tried a search, but there seems to be a problem with the search box ???)

 

[KillerHERTZ]

Im having the same problem except mine has completely failed, im guessing I need a new rear SAM...

 

[Barachello]

I'm honestly hoping that I dont have to go down that route !

I can't understand why the first bulb in the 'loop' is flashing whereas the second one is fine ?

 

[KillerHERTZ]

A few months ago I had one of the rear plate bulbs (left also) ultra bright and the other very dim until it went pop.

Loads on eBay, I might have to bite the bullet.

 

[Barachello]

which bit needs replaced though ?

The whole thing, or just a particular part ?

 

[KillerHERTZ]

Just the rear SAM as far as im aware. I must admit I havent looked into it that much so far.

 

[Barachello]

I'm assuming this is the SAM unit ?

 

[Barachello]

Is there another option to replacing the SAM ?

For instance, finding another power source for the bulb ?

 

[Barachello]

If a replacement SAM is bought, does it require programmed ?

 

[KillerHERTZ]

Nope, it should be plug and play as long as its from the same model

 

[Barachello]

They are from the same car, both c270's but they are different part numbers and SW and HW numbers

 

[E270 Owner]

Check the voltage and earth at the bulb contact points with a digi multimeter
If its a good earth and constant 12v supply get oem bulbs from Mercedes

They can be very fussy on wattage and voltage

 

[Barachello]

That would be a cheaper option first I suppose.

I can get a SAM for £60, which isn't too bad so I may as well have a stab at the bulbs first

 

[KillerHERTZ]

Make sure its a CLK one and not a C Class at the very least.

 

[Barachello]

Do you mean, make sure it is a c class and NOT a clk one?

My car is a c class saloon, and the guy breaking his car is a c class saloon as well

 

[KillerHERTZ]

Sorry, for some reason I thought you had a CLK doh!

 

[Barachello]

It doesn't take much to confuss me ........

 

[davidsw]

Just to confirm suspicions , I had exactly the same problem with number plate bulb and it was the rear SAM unit at fault .About £300 fitted if I remember correctly.

 

[Barachello]

ouch

 

[Barachello]

Bit of a strange one.

Nearly 3 weeks ago I bought a second hand SAM unit, and planned to fit it a couple if days later. The day after buying it, the malfunction indication on the dash disappeared ??

It stayed off, with the bulb working normally right up until yesterday, when it displayed the malfunction again.

However today it is away again ?

I am beginning to think it is a loose wire as opposed to a dodgy unit ?