Alternator wiring

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JerryMaidstone
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Alternator wiring

Post by JerryMaidstone »

Hi All, A flat battery led me to check if my fan belt had snapped, no. What I did find was evidence of a small fire that had destroyed the wiring on the back of my alternator. There are/were three wires. One small blue wire that goes to the top spade terminal, which is still connected, one thicker brown wire to the middle and another thicker brown wire to the bottom terminal. There isn’t a multi plug.
Can anyone tell me which brown wire goes on which terminal and should there be a multi plug.
Also, there is what looks like a diagnostic plug fixed to the alternator. Is it a diagnostic plug, what’s it for?
Many thanks, Jerry.
1984 1900cc water cooled petrol

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bigherb
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Re: Alternator wiring

Post by bigherb »

Yes, there should be a multiplug. It should also have red wires. The two larger wires (which should be 2.5mm2) are run in parallel from both of the larger terminals (they are connected inside the alternator) to the starter motor battery terminal.
The diagnostic is for connecting to the TDC sensor on the flywheel.
1982 Camper 1970 1500 Beetle Various Skoda's, Ariel Arrow

JerryMaidstone
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Re: Alternator wiring

Post by JerryMaidstone »

Thanks for replying, are you saying that the two larger wire can be connected either way round because they join together once inside the alternator body?
Red/brown? They are fire damaged

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bigherb
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Re: Alternator wiring

Post by bigherb »

JerryMaidstone wrote:Thanks for replying, are you saying that the two larger wire can be connected either way round because they join together once inside the alternator body?
Red/brown? They are fire damaged

Yes, you can see they are joined the small terminal is insulated from them.
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1982 Camper 1970 1500 Beetle Various Skoda's, Ariel Arrow

JerryMaidstone
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Re: Alternator wiring

Post by JerryMaidstone »

Thanks. Tomorrow’s job

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