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Discussion Starter #1
Hi, I've got a battery light come on, bought a new battery and it's still on. The battery will not charge. I've had the alternator tested and it's fine. I'm really am stuck.
 

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Discussion Starter #4 (Edited)
Still got this problem. Cars been sitting for a while. Charged the battery and done a fault scan. The car did have a front end accident before and have repaired it but these faults are present. The fuse box was removed so I'm thinking a plug is not connected? I have checked the loom and seems fine.The battery light is on and battery going flat quickly, engine managment light on, vsa light on
 

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Discussion Starter #6
The battery is NOT getting charged, when the engine is running.

Where is the output from the Alternator going?
I removed the alternator and had it checked and it's in good working order. Not sure about where the output from the alternator is going
 

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Is the battery earth strap okay?

Remove, clean and emery the chassis fixing.

Sent from my LG-D855 using Tapatalk
 

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It is easy to check how well the alternator is functioning by simply measuring the battery terminal voltage with the engine running at 1500/2000RPM and all the lights, HRW and blower motor all turned on full. You should see at least 13.8V (ideally up to 14.4v), which shows the alternator and wiring are in a reasonable condition.

The output from the alternator doesn't HAVE to be going anywhere... it can simply be feeding into an open circuit (like a 13A socket in your house if nothing is plugged in).

Sounds like a possible earth fault to me... as already said, check/clean the one from battery to chassis, plus the one from engine to chassis as well.
 

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Discussion Starter #10
It is easy to check how well the alternator is functioning by simply measuring the battery terminal voltage with the engine running at 1500/2000RPM and all the lights, HRW and blower motor all turned on full. You should see at least 13.8V (ideally up to 14.4v), which shows the alternator and wiring are in a reasonable condition.

The output from the alternator doesn't HAVE to be going anywhere... it can simply be feeding into an open circuit (like a 13A socket in your house if nothing is plugged in).

Sounds like a possible earth fault to me... as already said, check/clean the one from battery to chassis, plus the one from engine to chassis as well.
Alternator has been checked and is fine. I thought earth fault too checked the engine to chassis earth seems fine even sanded the contacting side
 

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Discussion Starter #11
Is there a fuse in the cabin I should check? I've checked the ones in the engine bay and all are fine.
 

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Alternator has been checked and is fine. I thought earth fault too checked the engine to chassis earth seems fine even sanded the contacting side
It didn't need to be removed and sent off to be checked... checking it in situ (as I described) would have been much easier and would also have confirmed the connectors and wiring were serviceable. If you took your car to an auto-electrician then this is what they would do first (even if you told them the alternator had been tested!). How was the alternator tested?

I'd explain other tests, but I'm guessing you don't have a voltmeter?
 

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Discussion Starter #13
It didn't need to be removed and sent off to be checked... checking it in situ (as I described) would have been much easier and would also have confirmed the connectors and wiring were serviceable. If you took your car to an auto-electrician then this is what they would do first (even if you told them the alternator had been tested!). How was the alternator tested?

I'd explain other tests, but I'm guessing you don't have a voltmeter?
Alternator was bench tested, my father has a volt meter I will get him to

It is easy to check how well the alternator is functioning by simply measuring the battery terminal voltage with the engine running at 1500/2000RPM and all the lights, HRW and blower motor all turned on full. You should see at least 13.8V (ideally up to 14.4v), which shows the alternator and wiring are in a reasonable condition.

As you suggested. Any other checks I should do while I have it? Thanks
 

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The alternator has only one cable coming from it and it goes to the battery.
This connected to the battery via the red cap and is also connected to the main power harness.

The alternator is mounted against the engine his is grounded.

The fact that you have the battery light means the following

Charging system fault

Charging system fault can mean
Alternator voltage too low
Alternator voltage too high
Alternator current too low
Alternator issue
Battery issue
 

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with engine stopped
check the voltage at the alternator and do the same check at the battery terminal the voltage should be more or less the same
start the car and do the same checks

if voltage differs from alternator reading and battery terminal ( 13.8 - 14.4v at alternator but showing less than 13v at battery ) your wiring is faulty or you have an earthing problem

if voltage is the same at the alternator and the battery terminal but reading less than 13v you have a faulty alternator even though it has been bench tested i would say it's still faulty

a faulty earth strap tends to also affect the speed the car will turn over when trying to start it or all the lights go dim and you get just a click even though you know the battery is fully charged when you press the start button

if the car turns over just fine with a good battery the chances are the earth strap from chassis to engine / battery to chassis is fine but worth checking any way

the other thing to check is the 12v feed wire coming from the ignition to the alternator if there is no voltage on this wire the alternator will not work
in the old days the 12v feed wire was wired through the battery indicator light on the dash but now on modern cars i'm sure it's fed from the ecu somebody with more knowledge on the subject will be along to explain
 

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Discussion Starter #16
For anyone who has the same problem it was a 10amp fuse under the dash on the drivers side
 
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