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Alternator not working

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Good. Set it to measure 15V DC. Feel down the back of the alternator and find either a squarish plug with a wire clip over it or a big terminal, both with two thick brown wires connecting to them (two different styles of alternator connection). If it's a plug, whip the clip and cover off but leave it plugged in.

Start the engine and measure the voltage from the thick brown wires to the engine block - should be over 14V with the engine revving (careful, the alternator is connected to the battery - don't short anything and mind the pulleys/belts/fan)

Also on the back of the alternator there should be a thinner brown/black wire. Check the voltage of this wire to the block too. This should be the same.

Lastly take the warning light block out, take the charge warning bulb out and check the resistance of the filament - should be "something".

Let us know the answers.

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If this was while revving the engine, then the alternator is not charging.

Take it out and get it recon'd, either yourself or by an auto electrician.

^^^^ Wot Gromit sed. The regulator / rectifier electronics are knacked. Gromit's Illustrated How To is here :)

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