Weird Battery Light Problem

[Swervin_Mervin]

Last 2 days my battery light has been on at startup and until today was staying on for a few miles before going off.

Odd, methinks. Today it stayed on for 20miles on the m-way to my mum & dad's. Got the multimeter on it when I got there and the Batt was fine and it was increasing the reading when started up and revving.

Now the alternator has aalready been done 18months ago and it was a brand new one that I managed to get. Tested it with my multimeter at home and it's reading 12.5V across the terminals when off.

Then it's reading 13.2 at idle and 13.8 when revving. Surely if the alternator wasn't working the battery light wouldn't be going off after a while. :?

Anyone got any ideas what it could be? When I came home it stayed on almost all the way 'til I blasted some 205 full of chavs away, and then it went off. :?

[BRUN]

voltage seems a little low mate tbh

i get about 14.6v at idle

[Swervin_Mervin]

It's bang on the money according to Haynes though and is obviously being charged by the alternator as it goes up. WTF is going on with the light? :evil:

Just going to check it now from cold as per Haynes.

[dannyb1986]

matt on here had problems with his battery light goin on and off, his was the alternator, i thinks its just on its way and not gone completly, his light used to come on when he had full lock on, you could try that and see if it comes on? also check that the wirings not loose on the back of the alternator!

[BRUN]

the minimum you want mate is 13.5v under heavy load, mine stays above 14v all the time

[Lunner]

I recon battery is on its last legs

Seems to be loosing charge when stood for a while, and obvously the drain on it when starting the car is mnaking it low and making the light come on, and its taking a bit of charging to get it charged back up

[richy]

u need to test it under load mate, stick lights, radio, heated screen etc on then see what u get, also there could be a drain on it anyway, take earth lead off and stick multimeter in on ampage to check, also daft as sounds just check the lead from battery to alternator as they can come loose or start to break off

[Swervin_Mervin]

Well Haynes says to check it when not used for 6 hours so I did that yesterday morning. 12.5V without the engine on and then 14.4V with it on.

No battery light at the time.

This morning batt light was on so I tested it and 12.5V off, 12.2V on.

However, once warmed up I took it to 7k and the light went off and it's now charging at 14.4V again. :?

I suspect a faulty wire from the alty to battery. I also noticed something like a loose clamp on the back of the alty.

Could someone please take/post a picture of that area so I can see what it should look like? Looks like it hasn't been put back together right by the garage that fitted the PAS pump to me.

[summeh]

alt is a bitch of a job, hope u dont have to take it out.

[Swervin_Mervin]

Alty is fine. I think it's the batt-alt lead.

Anyone got a pic of the anlty in situ?

[Swervin_Mervin]

C'mon peeps, someone must have a pic.

There's a bolt on the back of the alty and there's a piece if angled metal that's bviously designed to clamp round something. Bolt hole through it and 2 folded over sides that form a right angle. This is flapping about on mine and I remember from fitting the alty that this wasn't the case.

[Swervin_Mervin]

Well, I have rung vehicle electrical in Stockport and they're going to have a quick look on Saturday morning. It was off this morning but started flickering if I did between 2.5-3k rpm. :?

Then it eventually stayed on, 'til I ragged it up to the red line and then it stayed off. :lol:

I told the guy the symptoms and he said it seems really weird. Suspects that something is loosethat the garage didn't tighten back up properly. Might have a squiz this evening.

[Rajk]

check your battery connectors as they tend to be shite at the best of times, best bet is to change them for regular ones. The metal ones that do up with spanners, the plastic connectors are poo!

[Swervin_Mervin]

Well, it was checked out and it's the alty on it's arse basically. He said it looks very aged to say it's only 20months old. He blamed the lack of the weathershield round the rad.

So that's a new on being fitted wednesday. Then I'll make a shield up for the alty myself. :roll: