Fiesta mk4 diesel - Reverse light switch

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Wed 16 Feb 2011 14:41
Fiesta mk4 diesel - Reverse light switch - pullgees
I assume it is the switch, I've checked the bulb and fuse, both are okay.
This switch has a bunch of wires going into it, it is surrounded by a metal bracket held on by two nuts and the switch itself looks to be held on by a couple of Torx bolts. I cant see any reason why this rather big u-shaped metal bracket is there, except to be in the b***** way.
The question is how straight forward a job is it, are there any snags I should watch out for?
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Wed 16 Feb 2011 15:09
Fiesta mk4 diesel - Reverse light switch - Englishbullterrier

Hmm......my Escort had a similar problem. Switch was on top of the gearbox, just under the fuel primer/filter, held in by 2 torx bolts but ONLY had 2 wires going to it (all that's necessary for a switch). Are you sure it is the reversing light switch you're looking at ? .......ebt

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Thu 17 Feb 2011 12:28
Fiesta mk4 diesel - Reverse light switch - pullgees
There are two types mine is what Haynes calls 'the multi functional switch', it does other things of which I have no idea.
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Thu 17 Feb 2011 12:38
Fiesta mk4 diesel - Reverse light switch - Englishbullterrier

Very interesting, would love to know or see the circuit diagram.....

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Thu 17 Feb 2011 16:56
Fiesta mk4 diesel - Reverse light switch - pullgees

Here it is seekpart24.com/metzger/switch-reverse-light-912047...2

Edited by pullgees on 17/02/2011 at 16:57

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Thu 17 Feb 2011 17:13
Fiesta mk4 diesel - Reverse light switch - Englishbullterrier

Very interesting. I can think of no reason why there are 4 connections to simply turn on 2 bulbs in parallel.

The bulbs will be earthed in the light fittings so normally +12v would be supplied, via a fuse to one side of the switch. When reverse is engaged, the switch points "make" and send the +12v to the non-earthed side of the bulbs, and hey presto, let there be light !!!.....ebt

(at least that's what happens on my '97 Escort)

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Thu 17 Feb 2011 18:45
Fiesta mk4 diesel - Reverse light switch - elekie&a/c doctor

The reverse light switch on these is a double action switch.One set of contacts are for the lights and the second set are for the neutral position of gear shift.Signals the engine ecu when not in gear.hth

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Thu 17 Feb 2011 18:58
Fiesta mk4 diesel - Reverse light switch - Englishbullterrier

The reverse light switch on these is a double action switch.One set of contacts are for the lights and the second set are for the neutral position of gear shift.Signals the engine ecu when not in gear.hth

Ah thanks, I understand now. I (mistakenly) assumed this was an older car that didn't have an ECU. What years was the MK4 made then ?.....ebt

Edited by Englishbullterrier on 17/02/2011 at 18:59

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Thu 17 Feb 2011 19:17
Fiesta mk4 diesel - Reverse light switch - pullgees
Well this is all fine and dandy and very interesting but is this job fiddly.
The reason I ask is because I read somewhere (a bit vague on this) there is a little rod to connect up and while you are doing this oil is gradually dribbling out all down your sleeve etc.
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