Alternator Red wire

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bigblue
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Alternator Red wire

Post by bigblue »

Hi folks,

Just noticed that my alternator red wire isn't connected. Is to the alternator but not the other end! Found this as my battery keeps going flat, not charging? Would this be the cause?
All connections are good at the battery end and starts great when charged.

Does anyone have a pic showing where the red wire should connect?

muchos grassias... :ok
Last edited by bigblue on 10 Jan 2014, 14:31, edited 1 time in total.

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ninja.turtle007
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Re: Alternator earth wire

Post by ninja.turtle007 »

Earth wire? I thought is was earthed through it's casing?

Have you checked the voltage at the battery with the engine running? Should be around 14v.
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bigblue
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Re: Alternator earth wire

Post by bigblue »

Van won't start now until I charge the battery!

Seems the battery isn't charging. Connections are good at the battery end so looked at the alternator and notices a wire unconnected. Presumed it was the earth. I'll try to get a photo up.

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Re: Alternator earth wire

Post by bigblue »

Sorry, it's the red wire that's disconnected. Attached to the alternator but not the other end. Where exactly does it connect?

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Oldiebut goodie
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Re: Alternator Red wire

Post by Oldiebut goodie »

Depending upon what engine, direct to the battery on a diseaseal. I believe to the starter connection from the battery on a petrol - someone will be along to say I should think.

(This is why we say to put what you have in your signature then we don't have to run around the houses guessing)
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ninja.turtle007
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Re: Alternator Red wire

Post by ninja.turtle007 »

Oldiebut goodie wrote:Depending upon what engine, direct to the battery on a diseaseal. I believe to the starter connection from the battery on a petrol - someone will be along to say I should think.

(This is why we say to put what you have in your signature then we don't have to run around the houses guessing)

Direct to battery on both.

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Oldiebut goodie
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Re: Alternator Red wire

Post by Oldiebut goodie »

Strange - the wiring diagrams show it as going to the starter and don't show it going forward to the battery on petrol vans. Also Bentley shows it attached to the starter solenoid.
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itchyfeet
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Re: Alternator Red wire

Post by itchyfeet »

Correct to the starter on petrol but he has a 1.9 n/a 1Y its in his garage profile
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Oldiebut goodie
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Re: Alternator Red wire

Post by Oldiebut goodie »

Nothing in his post though. We are not all mind readers. Image
My post covered it though.
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MidLifeCrisis
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Re: Alternator Red wire

Post by MidLifeCrisis »

I've yet to confirm this by rolling around under the van chasing wiring looms but I think that on my '84 petrol DF/DG that the wire from the alternator goes to a positive 'post' in the little black box in the engine bay (the box with all the other connectors/relays in it).
A wire then runs from that post to the starter motor ....
... But that could all be rubbish!!
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RedGus
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Re: Alternator Red wire

Post by RedGus »

Oldiebut goodie wrote:Strange - the wiring diagrams show it as going to the starter and don't show it going forward to the battery on petrol vans. Also Bentley shows it attached to the starter solenoid.

On mine (CU) there are two red output wires (2.5 sq mm from memory) with a large spade each onto the alternator and a ring each onto the starter solenoid lug. The rest of the route to the battery, up front in the petrol vans of course, is via the heavy (25 sq mm?) starter cable, in the normal way.
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RedGus
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Re: Alternator Red wire

Post by RedGus »

Oh, and don't forget to charge the battery off the van before you try to charge it with the alternator. If you try to charge a completely flat battery using the alternator, you run the risk of doing it some major damage (the alternator, that is).
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itchyfeet
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Re: Alternator Red wire

Post by itchyfeet »

MidLifeCrisis wrote:I've yet to confirm this by rolling around under the van chasing wiring looms but I think that on my '84 petrol DF/DG that the wire from the alternator goes to a positive 'post' in the little black box in the engine bay (the box with all the other connectors/relays in it).
A wire then runs from that post to the starter motor ....
... But that could all be rubbish!!


The important bit is that the all connect together with the right guage wire

Anyway he has a Diesel so petrol wiring debate is not helping :D
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Re: Alternator Red wire

Post by bigblue »

OK folks. Thanks for all your replies. It's a, 89 1.9 petrol DG watercooled engine. I've been told the red wire from the alternator should connect to the solenoid but not sure which connection of the three.
A. The rear 'spade' connection that goes to the starter.
B. The front small bolt.
C. The centre big bolt.

Can anyone direct me to a wiring diagram?

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kevtherev
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Re: Alternator Red wire

Post by kevtherev »

There's a great diagram in the Haynes. :ok
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