Coolant light problem Mercedes 300E 1992 110,000 mi.

Dashboard cooling light (yellow picture of water in a "can") comes on faintly then gets brighter as i drive but never fully bright. I live in
California in a cool climate..Palos Verdes on the ocean. Indicator doesn't register abnormal high tempersture...around 80 of 120...where it has always been. I feel if I drove it longer i might have a problem. But 10 miles it should be fully heated or overheated...correct? Car works fine..I don't drive it over 10 miles before I stop. There is water in the well that I can see when I take the cap off (I wait till its cool) ...I ovefilled it a bit to see if that would help...good move? Thanks for anything you can help me with. I plan to bring it to a mechanic but I'd like your input first so I sound somewhat knowledgeable. Again, thanks in advance! Frank Does the light come on if it is overheating or if the water is low?
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snipped-for-privacy@aol.com wrote:

It is a faulty sensor on the reservoir. Try replacing it (or your fuses), strip fuses cause strange electrical gremlins. The sensor is supposed to show level, when low it turns on.
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I had similar issue. Problems was some crud and corrosion on the connector to the sensor. I cleaned this up and problem went away. Peter

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Peter, Thanks! Where is the sensor and what does it look like? Frank in Palos Verdes
Peter W Peternouschek wrote:

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It is located on the front of the coolant reservoir tank. You should see the wires going to it and the connector from the front of the car. Peter

in
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Peter, Thanks very much! I tried to pull the sensor off after having unlached it and it broke (the plastic) in my hand. I cleaned it and reconnected it (even) broken and the light went out and all is fine. I haven't gotten down to where it connects below but I assume it is just a connection I can reach...? I now have to find a reasonable place to buy the sensor. Any suggestions/.... you have been soooo helpful so far. Merry Christmas. Frank Malone
Peter W Peternouschek wrote:

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snipped-for-privacy@aol.com wrote:

I buy all my MB parts from Rusty at www.buymbparts.com. Great store and great help if needed.
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You probably don't have to replace the sender. I sounds like you broke the connector to the sender. As long as the pins make good contact you are probably ok as is. For parts at good prices and no sales tax I prefer these guys. I have dealt with them many times with excellent results. https://www.autohausaz.com / Good L:uck Peter
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