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Discussion Starter · #1 ·
Hi guys ;)

The story
(skip if you want to)

Well my battery ran flat again yesterday, had to get a bump start outside a customer's house (the customer helping to drag my car up the hill so I could start it, not fun)...

I assumed it was because I'd let the battery run flat by leaving the interior light on, then not driving the car enough to charge it back up, as I've only been doing very short trips lately.


I put a fully charged working battery in the car just now, and ran the car. My MPG meter showed the battery voltage at 12.5, when it should be around 13.8 when running. I confirmed this with my multimeter.... the alternator certainly aint putting anything out.


The alternator in question is only a year old, and has been working fine till now. The alternator had to be removed and replaced again when getting to my lambda sensor not long ago, so is it possible that the wiring is at fault? A quick glance tells me that the wires are a little corroded. I need this working urgently - while the car runs now with the charged up battery I'm doing a fair amount of very short journeys requiring the starter motor to be run often, so obviously I don't want the battery to be dying on me.


The question

Which way round should the wires on the alternator be? At the moment I believe the thicker one is toward the front of the car, with the smaller one on the connector further back. I'm wondering if these were put the wrong way round when the alternator was reconnected before...

Thanks in advance!
 

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Chris,

Brown wire goes to engine compartment fusebox (by look on the connector this one is thicker, bigger), and brown/yelow goes to passanger compartment fusebox (by look on the connector this one is thiner, smaller).
 

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Discussion Starter · #3 ·
Thanks for that :)

Right, it appears the alternator has the wires the right way round, and after a bit of fiddling to get my probe onto the alternator connector with the engine running (trying to avoid the hot exhaust) it is putting out 14v.

So the alternator works, woot. Unfortunately the battery is still showing only 12v... does this mean the alternator and battery are not connected together properly? I've checked all fuses in the engine bay and they appear fine.

If it's a break in the wire... can I just connect the alternator and battery together directly for the moment?
 

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Discussion Starter · #4 ·
Just had a quick google and it seems quite a few people just run a 8awg wire from the alternator to the battery with an inline fuse, would there be any problem doing it on the 200?

I wish I didn't have to go out tonight... but I'm supposed to be at a meeting in about 15 minutes :err: so I'll have to drive soon.
 

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Discussion Starter · #8 ·
Thanks! Right well it seems that there's just an 80amp fuse between the battery and alternator...so I'll get some wire and an inline fuse tomorrow and wire it straight up. Less to go wrong that way ;).
 
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