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The speedometer in my 745 with 160K has been jumping around a little on the highway. The cruise control would try to follow the erratic speedometer, then disengage. I figured the worst, that the speedometer head was failing. Today, the speedometer dropped to 0. When I hit a sharp bump in the highway, it would re-set itself and act ok for a few miles. I suspected a broken wire at the sending unit. What I found was a burnt wire at the sending unit. The wire had grounded out on Volvo's safety wire. I suspect that the safety wire slowly eat throught the insulation on the wirin, causing it to ground out. The plug was melted and an inch or so of insulation on the green stripe wire. I have rigged it together and sealed it with di-electric grease. I hope the short has not damaged more stuff. The speedometer seemed normal on my short test drive. I wanted to warn you to remove the safety wire or make sure it is not cutting into the two wires on the sending unit at the back of your rear end. I will check my 940 asap.

Pat