fiesta mk 3 battery warning light on

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Sun 18 Feb 2007 19:12
fiesta mk 3 battery warning light on - milkyjoe
hi, ive got a prob with the battery charge warning lamp on my fiesta ,it stays ON when i switch the ignition off and remove the key, the alternator is functioning with the engine running and the battery warning light goes out, ive looked at the wiring diag and as far as i can make out there is an in line diode in the warning bulb connection that comes off the alternator multi plug could it be that that has failed causing a reverse voltage? if so how do i replace the diode?
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Sun 18 Feb 2007 19:45
fiesta mk 3 battery warning light on - Screwloose
milkyjoe

Right beside the starter there's an in-line joint in a blue wire. Separate the two halves and see if the light goes out. If it does; then you have a field diode gone in your alternator.

Get the alternator cabling checked before fitting a new one.
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Sun 18 Feb 2007 19:49
fiesta mk 3 battery warning light on - milkyjoe
.*********
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Sun 18 Feb 2007 19:50
fiesta mk 3 battery warning light on - milkyjoe
cheers, yes the light does go out ,does that mean the alternators had it?
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Sun 18 Feb 2007 20:01
fiesta mk 3 battery warning light on - milkyjoe
i only got it last week from the breakers every thing was working fine till this afternoon im sure i wired everthing up ok,even isolated the battery when i fitted it
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Sun 18 Feb 2007 20:19
fiesta mk 3 battery warning light on - Screwloose

That's the reason for the previous comment re getting the cabling checked. Either there's a cable fault, or the battery was low when you fitted it. A lot of alternators die shortly after fitting.
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Mon 19 Feb 2007 01:07
fiesta mk 3 battery warning light on - milkyjoe
as far as i know the multi plug is fitted correctly at the alternator and secured with a small latch(wire clip) and the other end is fastened tightly to the starter motor solenoid thats about it really and the push fit connector to the warning bulb is secure and the battery was fully charged
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Mon 19 Feb 2007 01:11
fiesta mk 3 battery warning light on - milkyjoe
i put a voltmetre across the battery and revved up and the reading was good ,about 13.5 volts,i assume it still functions somewhat with one duff diode?
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Mon 19 Feb 2007 09:08
fiesta mk 3 battery warning light on - madf
If it helps, I had this problem on a Triumph 2500PI and ran it for 4 years like that...with no problems and the same battery.

madf
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Thu 22 Feb 2007 17:02
fiesta mk 3 battery warning light on - milkyjoe
i left the alternator connected up over night with the dodgy diode, it sucked the battery dry by morning, ive got it on trickle charge at the mo hope it aint shot, oh replaced the alternator forthwith
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