Flakey Speed Sensor on 07

[Rick J Fisher]

While driving; speedo goes to zero, transmission locks in 5th, no exhaust brake or cruise control, light says Missed Shift. Killing power at battery switch resets it. OK for 5 minutes or two hours then fails. Sometimes does not fail the whole way home. Milliemae had similar problem, had speed sensor replaced to fix. I would like to replace it myself. Where is it on 400ISL and what does it look like?

[tmh462]

Most of them are on the transmission where the output speed can be measured, say near a drive shaft or output shaft. It should be a round electronic piece with two wires in a plug, held in the transmission by a clamp bracket and small bolt. If you're sure that's your problem, you can go buy a new one, and crawl under the coach to look for the part that looks like the one in your hand.