Hello everyone,
My in-dash thermometer is reading between 40 and 48 degrees consisatntly since my return from florida (1200 miles right through@27mpg!). I was wondering if anyone has encountered this before. Maybe the car doesnt like being back in the north east and is protesting the sub freezing temps around here?

Thanks in advance,
Greg

 

first, try checking your thermometer. its located under the front bumper right behind the license plate.

 

My 300TE has now read 58°C for a year now (in the UK?!?! Never!)
It started being only 2-3°C out then got worse over a few months acting like a calender rather than a thermometer.
Guess the resistivity is too great. The thermometer is in good shape and clean behind the licence plate.

Not too expensive, but it does plug directly into the back of the dash, and I have not a clue as to how to install this part!

Any ideas out there?

 

Mercedes chosen location for the ambient temperature display sending unit shows how difficult it is to place the sender where it won't be affected by engine heat. This location also makes the sender very succeptable to damage. If a car parked in front of yours backs into your car even gently, it can cause the display to read erratically. The accepted easy way to repair the problem is to call Rusty @800-741-5252 and get a discounted price for a new sender. It will be sent from a dealer near you. The sending unit comes with a very long wire intended to reach the back of the dash instrument cluster. Splice the new wire onto the existing wire and your display will work perfectly until someone backs into your car! P.

 

Well, after a little time and investigating I figured out what the problem is.. excessive resistance in the line. I've noticed in this car (which is almost as bad as my '02) there is the tendency for corrosion on any exposed connector. This probably has to do with being so close to the ocean and living in the rust belt too. So all these wonderful large pin connectors that MB used so extensively, allow enough air contact and thus corrode quite quickly. I use a lot of dielectric grease grease to prevent corrosion but its a losing battle (my Over-voltage protection relay was covered in the green nasty). Does anyone else have similar problems? Anyone have a better method for prevention?

Thanks,
Greg