Mazda 626 (2000 - 2002) - 2000 2.0D Blown Headlight Bulbs and 27volts

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Thu 4 Dec 2008 12:32
2000 2.0D Blown Headlight Bulbs and 27volts - markeastwood
Before I blow £250+, am I right in thinking that if the battery's showing 27v and the headlights have popped then the voltage regulator's knackered and the alternator needs replacing?
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Thu 4 Dec 2008 12:39
2000 2.0D Blown Headlight Bulbs and 27volts - RichardW
I think 27V is a pretty good sign that something is up with the voltage regulation! You might be able to get the alt fixed at a local auto sparks, rather than replace.


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Thu 4 Dec 2008 17:36
2000 2.0D Blown Headlight Bulbs and 27volts - Peter.N.
Certainly seems like it. I would question whether 27v is correct though as something would be cooking at that voltage not least the various Ecu's. 27volts is enough to destroy most of the electronics and if the battery had that voltage across it, its resistance would be to high for it to function, check it again, should be around 14 volts, anything in excess of 14.5 is to much.
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Thu 4 Dec 2008 17:44
2000 2.0D Blown Headlight Bulbs and 27volts - mfarrow
ECU would be self-regulating, though agreeably it's at the top end of what it will take.
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