[Mk2] [Turbo] Battery not charging

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Monkey
Posts: 64
Joined: Wed May 06, 2015 12:56 pm

[Mk2] [Turbo] Battery not charging

Post by Monkey »

I seem to have the illusive charge circuit fault.

Battery is not charging, but it ls not draining power either, seems when the car is running there is enough power from the alternator to power everything but not charge the battery. Went on a 20 min drive with everything turn on and it was fine.

I have checked the eng-ig, Alt Sensing, AM2 fuses (well all of them) i have replaced the ignition Relay, because the test in the service guide suggested it was faulty, and its not.

Also my reverse lights are not working, and i read that it could be related, but i cant see how, also i have read about swapping rhe fan relays, there are 3 and they are different shapes?!?!

I am going to check the 3 pin plug on the alternator tomorrow.

Anything else i should look for?
SonicSW20
Posts: 3681
Joined: Mon Nov 29, 2010 7:54 pm

Re: [Mk2] [Turbo] Battery not charging

Post by SonicSW20 »

How old is the battery? Could just be that the battery is dead.
mr2garageswindon
Posts: 282
Joined: Wed Oct 15, 2014 3:02 pm

Re: [Mk2] [Turbo] Battery not charging

Post by mr2garageswindon »

What volts reading across battery with and without engine running? Does the battery light illuminate when just ignition on?
Most likely the alternator is just pushing out enough to keep it running but not charging it.
Check engine earths too.
Monkey
Posts: 64
Joined: Wed May 06, 2015 12:56 pm

Re: [Mk2] [Turbo] Battery not charging

Post by Monkey »

Gazza_DJ wrote:How old is the battery? Could just be that the battery is dead.


Brand new

mr2garageswindon wrote:What volts reading across battery with and without engine running? Does the battery light illuminate when just ignition on?
Most likely the alternator is just pushing out enough to keep it running but not charging it.
Check engine earths too.


Battery reads 12.2 volts, when cranking the volts drop then return to 12.2 whilst it is running. As i switch different things on (lights etc) the voltage drops and then returns to 12.2 when switched off.

Battery light is not on.

I am confident the alternator is fine, but i will be trying to check tonight.

This is the thread i was looking for,

http://www.imoc.co.uk/forums/viewtopic.php?p=966937
mr2garageswindon
Posts: 282
Joined: Wed Oct 15, 2014 3:02 pm

Re: [Mk2] [Turbo] Battery not charging

Post by mr2garageswindon »

That is just battery voltage and being a new battery its what I would expect. Battery light not on while running or doesn't come on at all?
Have you un plugged the reverse light switch to see if that makes any difference?
Monkey
Posts: 64
Joined: Wed May 06, 2015 12:56 pm

Re: [Mk2] [Turbo] Battery not charging

Post by Monkey »

mr2garageswindon wrote:Battery light not on while running or doesn't come on at all?


It when on ign 2 it doesnt light, start the car and it flashes up and then goes out and stays out.

Here is a video

https://youtu.be/ZGp-p-3ixC8

Thats with the reverse light switch unplugged

mr2garageswindon wrote:Have you un plugged the reverse light switch to see if that makes any difference?


Just tested reverse light, switch is fooked did the paperclip test. So i'll order that in the morning.

I pulled the Eng-ig fuse, fuse is good, put a volt meter on the power side of the termainal with the engine running, and its only receiving battery voltage. I didnt get a chance to get under the car to test the 3 pin connector on the alternator. Thats tomorrows job.

On a side note, how hard is it to find a metal uncoated paper clip round the house?
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