Coolant Light Dimly Lit
 

The coolant light comes on now occaisionally on my 1992 300E 4-matic. It's very dim, not really the full strength light you see at start up. But the coolant level is fine and the engine isn't overheating. Any ideas? I did recently have the coolant replaced at a Quick Lube kind of place and they put in a very green-looking liquid, opposed to what came out – which was much more clear. Is the type of coolant important and does using different types make a real difference to cooling efficiency?

go to your coolant resevior and unplug the low coolant level
sensor. dollars to donuts coolant is seeping out through the
sensor causing the dim lamp.

a new sensor, oring, and possible connector should take care of it.

as for the coolant check the threads on that issue. i usually
replace green stuff with the same and use the amber OE
coolant if thats what was in before.

Simple issues...your coolant level sensor is corroded...does that with age.

Look near the bottom of your coolant tank and the sensor has a electrical connection to it. Most likely it has gotten to the point where the coolant now seeps onto the terminal contacts and is causing the effect you describe.

As a temporary measure, you can clean the contacts and the sensor and get the light to go off.

This may get you by for a few weeks to a few months when the light starts to come back on, but eventually you will have to replace the sensor.

Fortunately it's not expensive. $40 (I think) and you can replace it yourself within 15 minutes. Did mine last year when the same issue occurred.

Check Fastlane at the top of the page to obtain the part. ;)

Coolant
 

Thank you very much, Devil!!!

Coolant
 

Thanks a lot G Benz!!

Todd

Don't worry too much about a dimly lit bulb. We have some members here like that. :D

my car is a 190e-1.8 1993 uk spec car.

i have the exact same problem which i noticed last night.

the coolant level light was on dimly and only noticeable at night.

the coolant level was fine and the car is not overheating.

so,thanks for the answer to my problem.

what a great forum!!:D :D