My outside temperature/thermometer gauge (LED) is reading about 70 degrees high. As winter approaches, I miss an accurate readout. Is the sensor behind the front license plate? Can it be replaced by a backyard mechanic like me?

Yes, and yes. Do a search for "thermistor" - I think there is at least one thread that lists the Radio Shack part number for said thermistor.

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It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D

you want a 3.3k thermistor (3.3k ohm =~ 25C or 77F)

To test the temp sensor - follow the wire, it leads to under the fuse box - unplug the two wire connector and plug a 3.3k ohm resistor across it - see if the display reads about 77F. If it does you need to put in a new thermistor.

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Daily Driver: 02 E430 4MATIC
In the family: '03 E500 // '04 ML500 // 64 220SE

Wow that's nice to know,,, are all MB thermisters the same? i.e. like ones for the W126's W140's W202's ,,,,,