Hi dave. Yes you are right, the sensor is located behind the front bumper. It is held in by a spring clip, ie a push fit. It is connected by two wires in a multiplug and easy to test with warm air etc. I have not known one to fail, but there is always a first time! The computer (the display) is easily removed, I would start there first. If you can beg borrow or steal one for a while, try swapping it over, see if it is the sensor for sure. If its not, then you will have to go on the hunt, find the sensor and try a swap again. If it is a wiring concern and nothing obvious, unless your are confident, then I would let a professional loose on it.
Paul
January 2008
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