I have the 1.8 2004c-max and had the same prob so I got a new switch from ford £11.00 I put it on works fine. To get at it remove the battery and then undo the 3 bolts at the bottom of the battery holder this lets you lift the holder to the right so you can get your hand in to undo the switch 22mm spanner anti clockwise. Not a lot of room and do not over tighten.
Richard
July 2010
Mine ain't working aswell. It's got to be the switch as i've done all the tests. Having a look through the net to see if someone stocks the "reverse light switch which goes to the gearbox reverse gear on the gearbox" without going to ford.....
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