Dead Speedo

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KDS
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Post Fri Sep 23, 2005 7:10 am

My speedometer died while the car was being repainted. The tach and other gauges still work fine. Fuse is testing okay. What should I be looking for?
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-KDS in Vancouver ('88 325i Touring)
E30Mark
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Post Fri Sep 23, 2005 7:59 am

First check the connector to the speed sensor on the rear diff, these corrode.

Also check the wiring from this connector, these also tend to break internally over time.
1 & 2 bed flats in Bournemouth areas, with parking
PM for details
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orangecurry
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Post Fri Sep 23, 2005 7:51 pm

top advice from Mark - my speedo went intermittent, then died. I fiddled with the cables out of the diff, and it came back... temporarily.

So I went to the scrappy today and found a diff speedo plug and kept as much wire on it as possible.

I then cut out as much wire as possible from my existing cable - from where the wire emerges from the body, connected in the 'new' cable and plug, and the speedo reads 100% of the time. (ok I've only done 10 miles since, but it proves the problem is cable/plug)

The length I removed runs over the rear axle, so might well have worn over time?
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Brianmoooore
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Post Fri Sep 23, 2005 9:05 pm

Trouble is, the cable you removed from the scrapper will have been work hardened by vibration as well.
You should have aquired the yellow headlamp connector and wire instead.
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orangecurry
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Post Fri Sep 23, 2005 9:51 pm

yeah that crossed my mind, but
a) it was fun
b) the donor car is one car up and balanced poorly, and the chances of me making it back home if I'd tried to get the bonnet open and get up there are.... small :eek:

I'll wait 'til it falls down (or my speedo stops again)

I remember you saying that in another thread (take the yellow one), but the fittings look slightly different, enough that I didn't belive you... sorry :oops:

I won't make the same mistake again, My Master. :D I have much to learn......
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Brianmoooore
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Post Fri Sep 23, 2005 10:15 pm

You only really need any two bits of wire with the right angled socket inner pieces on them. The yellow plastic bit is available on its own for a few pennies, from your local friendly dealer.