outside temp gauge
 

My temp gauge reads at least 10 degrees warmer than the outside temp rather consistently on my 98 E300TD. Is this a senser problem up front or is this culprit located somewhere else?

I have a similar problem, except that mine reads 10C lower. I suspect that it is the temperature sensor itself.

My LCD temperature gauge, has also started to darken in one corner, and as the weeks go by its getting progressively worse. I am sure that in a few more months it will become completely black.

The outside temperature sensor is close to $80.00. You don't even want to know how much the LCD display is. although a bit annoying, I can certainly live without this display. Its not worth the cost to me to repair it. but as the saying goes "Your milage may be different"

It doesn't bother me a lot either, but I would certainly rather not have the whole display go out. I wonder if this is an easy fix or not. Is this an MB tech matter or could a novice like me get at this? At $80, I'd like to give a shot. Thanks!

I just changed my outside ambient temperature sensor for one I picked up in a scrap yard ($20.00 Cdn), and it made no difference, The display was still indicating 10C Lower than actual ambiant. I went back to the scrap yard and bought a used LCD display for 50.00 Cdn. Changed my old, partially black display, and now everything works fine.

Moral of the story is that although unlikely, the display itself could be inaccurate, causing an erroneous readout. So if changing the sensor does not help, than its the display.

Phil

One thing about it, it has consistency at reading +10. I believe I'll just tolerate it at this point. Thanks!

Mine was also consistently reading 10C lower before I changed it. One thing I was thinking of doing was to solder a potentiometer in parallel with the two wires coming from the outside temperature sensor. I was then going to adjust the potentiometer until I obtained a correct ambient reading on the display. If yours reads 10C higher you would have needed to connect the potentiometer in series, not in parallel.

I could have used a fixed resistor, but I didn't have the resistance specs of the sensor, Thats why I was going to go with a potentiometer. As you now know, instead of the potentiometer trick, I ended up changing the whole LCD unit. That fixed the problem.

By the way, When I took the old LCD display out, I took it apart to see what caused it to go black at the bottom Left corner. I discovered that the display's miniature light bulb is DIRECTLY behind the black spot that developed, and that subsequently kept on expanding. So its likely that the heat from that miniature light bulb is what finally did the LCD display in.