Coolant Level Sensor

[Norris]

I wonder if anyone can help me !

My coolant level lamp keeps coming on intermitantly ( generally when i turn or go over a bump)

Recently had head gasket changed, head skimmed, changed radiator and viscous fan coupling. Chaged the sensor (the part inside the rad). Yet this light keeps coming on. Car runs steady at 80 (temp)

Is this light anything to worry about or is more likely an electrical fault?

 

[Norris]

Just to add, if i shake the car (rock) the light will flick on and off

 

[television]

Hi Norris. just asking but this does seem as though the coolant level is a little on the low side

 

[Norris]

nope its fully topped up

 

[anyweb]

is this a C series (w202) you never said ?

in mine the radiator expansion tank is above the radiator, and even though i thought the rad was full it wasnt, i had to make sure that the rad expansion tank was absolutely full before my light went out.

cheers
anyweb

 

[television]

By squeezing the big hoses at the top and bottom with the filler cap off will release any air in the system

 

[Norris]

yes sorry, its a C220. Thanks for the advice i will give it a try and let u know how it goes

 

[Norris]

Right

none of the above worked. The lights still coming on.

I have no visible leaks from the engine. Ive pulled out all the spark plugs and turned it over and i have no water coming up from the pistons.

But the car is very rough in idle

Has anyone experienced this kind of thing?

 

[type49]

Coolant & washer bottle are linked. Check washer bottle level & try again.

 

[Norris]

nah filled washer bottle up fully already

 

[Norris]

ive got no signs of water in my oil either (not creamy)

 

[bigasotonuk]

Coolant & washer bottle are linked. Check washer bottle level & try again.

My coolant light was coming on, and it was the washer bottle switch was faulty replaced it and it cured it . Really cheap to replace from MB

 

[JEZ.S320L]

My coolant light was coming on, and it was the washer bottle switch was faulty replaced it and it cured it . Really cheap to replace from MB

If this cures the problem, I bet NORRIS won't be too pleased having "......Recently had head gasket changed, head skimmed, changed radiator and viscous fan coupling. Chaged the sensor (the part inside the rad)......"

Oh dear! :cry:

 

[bigasotonuk]

My coolant light was on all the time though the bottle was full to brim. Went to MB and spoke to the parts man and he said that it would be the washer bottle switch (not the Coolant switch) as they were joined electrically. I thought 'he don,t know what hes on about'
I bought and replaced Coolant level switch and still the same so i went back to MB bought new Washer level switch and replaced it fault gone.
He may just have a dodgy connection on the plug to the Washer level switch i 'personally' cant see why you could,nt just short the Washer level switch plug out this 'should' extinguish the light and prove it is this switch at fault.

 

[Ian B Walker]

The sensors in the radiator on some 202's are a little prone to failure. Buy a new one (quite cheap) and try that.

 

[Norris]

Changed the sensor already.

If it aint one thing its another.

First needed to get head gasket changed, head skimmed. Then got it back radiater blew, so new rad and fan coupling, sinse then coolant level light wont (wouldnt) go off.

Dumped a bottle of k seal in it, light hasnt come on yet, drove it for couple of hours so hopefully thats sorted it.

 

[anyweb]

4 days ago or so my 'radiator hot' light was flickering as if it was about to come on (very slight flicker, and probably you wouldnt notice it) in my w202, i checked the coolant level and it was full, over the next few days it got worse with the light coming on FULL randomly (as original poster said, going over bumps and the like) and then going OFF again,

i replaced the coolant level sensor this morning and it seems fine ever since, havnt seen the warning flicker come back on, however while doing so i made sure to push the two wires in as they looked a little bit on the loose side, so either the sensor was on its way out or the wires connecting to it were/are corroding which is not unimaginable seeins as its a 12 year old car.

i'll post the mercedes part number of the part shortly, oh yeah one other thing, the new sensor had a very easy to see black portion (lead or something) in the bottom of the white sensor, whereas the old sensor did not, perhaps this 'stuff' had worn away (or floated away) and is/was the cause of the issue,

fyi

cheers
anyweb