Battery/charging light

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Evsi
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Battery/charging light

Post by Evsi »

Hi folks,

Just wondering if anyone can clarify my charge light theory. Voltage is sent via ignition switch to illuminate dash led and earths through alternator circuitry until engine starts, sending voltage back through exciter wire to cancel led? (as long as the system is in correct condition of course)

My charge light is constantly on even though it's charging correctly and wiring is ok and i'm struggling to solve it :(
It's not rust, they're heat blisters....

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kevtherev
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Re: Battery/charging light

Post by kevtherev »

My charge light came on for a while.. and it was charging ok.
ended in the alternator diode plate failure six weeks later..
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Oldiebut goodie
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Re: Battery/charging light

Post by Oldiebut goodie »

^^^^^^^WHS
If the alternator diode that the charge light is connected to is dodgy it could well still give a charge albeit not a full whack.
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jamesc76
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Re: Battery/charging light

Post by jamesc76 »

the charge light is a funny one really it has 2 12v feeds to it:

When you switch on the ignition the light illuminates as it battery voltage to it earth's throu the alternator, then once the engine is running the alternator should be kicking out 13.5 to 14.5 (ish) volts which is higher than battery voltage so the light goes out if there is an imbalance on either side the light will come on.

So what voltage is the alternator actually kicking out ???
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Evsi
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Re: Battery/charging light

Post by Evsi »

Thanks guys.

I'm getting 14.2v from the alternator which is why i'm confused. I changed the regulator just incase but no change.
It's not rust, they're heat blisters....

California Dreamin
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Re: Battery/charging light

Post by California Dreamin »

Diode pack failure is the percentage guess but don't eliminate the obvious...earths/feeds/battery terminals etc.

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Evsi
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Re: Battery/charging light

Post by Evsi »

Cheers Martin.

I don't usually get flustered with things like this, but the van is obviously upset with me :roll:
It's not rust, they're heat blisters....

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