c200-warning light for bulb failure

[sunil sood]

it comes on and then goes off while driving.

i have checked all the exterior bulbs which appear to be working including the number plate lights.

also the bulb wattages are correct.

any ideas as to what is causing this intermittent fault or is just down to the damp autumnal/winter conditions?. :?:

 

[sunil sood]

andy,

do have any idea why the above mentioned problem is happening and its cure.?

your comments would be appreciated

 

[KLP 92]

Sounds like one of your bulbs has a loose connection. Its basically making conatct with the terminals most of the time but sometimes it doesn't and your light comes on. Does it only do it when you hit the brake, or when the exterior lights are on, or when using indicators? If it happens with one of these check the buls and then cklean the conatcts and make sure that they are making proper conatct.

 

[sunil sood]

thanks for your comments-it happens only when driving and i hit the brake pedal-also it only appears to happen after a period of driving ,and never on starting the engine ,so that makes me think that the problem shows itself when the brake bulbs are hot.

 

[dieselman]

Probably the brake light switch.
The switches are two way flip / flop switches and use one set of contacts to light the bulbs and the other for bulb testing.

Worth changing the switch as they do burn out and are only a few pounds.

Also check the brake bulb holders as they can suffer poor connections, and make sure both brake bulbs actually work reliably. It is possible for bulb fillaments to be broken but make when cold.

 

[sunil sood]

dieselman,

thanks for your helpful comments.

any idea where is the brake light switch located?

 

[Aletank]

I had a similar problem with a side light bulb, It would be out with the warning light on, then after about 10mins of driving it would come on.
I heard somewhere that replacement bulbs you buy from Halfords etc are very very slightly smaller than genuine MB ones.
I bought a genuine MB bulb from the dealer (about £1) and its been OK since.
So if you find out which bulb it is, buy a bulb from your dealer

GOOD LUCK :wink:

 

[sunil sood]

the brake light bulbs on the car were from german and swedish-so as you say the merc dealer ones would be worth trying