Battery Light On

[Mike FR+]

Hi all

Driving home work tonight and my battery light came on, I nearly papped myself, the A19 was packed!

Anyway, I pulled over and turned everything on to see if it cut out but it was fine. I have started and stopped it a few times and had no issues. I have checked all of my lights, battery connections etc. It is starting as usual and driving fine.

When I start the car the battery light flicks on then off then comes back on permenantly.

Any ideas what might be up?

 

[MJ]

did you get my text mate?

 

[Mike FR+]

Yeah mate just replied. I have left it for a few hours and just been and started it again and it fired up as per usual. I turned everything on full blast and there was no lights dipping or change in engine tone, it was just normal

 

[lil3520]

I had this one night, pulled over and one of the belts had come off aa chap informed me.

 

[Mike FR+]

I have been out this morning, car has been sat for 12 hours, heavy snow etc and it started first time, no hassle whatsoever.

Think I am going to have to check all of the fuses in the fuse box on top of the battery and in the car itself.

 

[oldman]

does it not give a fault code when run vag-com.
not sure what manual says about the battery light

 

[Mike FR+]

Im going to stick vagcom on when I get in from work - half day cos of the snow.

I will check the manual, I am wary as to whether it will be the alternator as its 20 odd hours since the battery light came on and no adverse things happening

 

[oldman]

if battery is low, i always thought things like lights on and using elec window the lights would dim, but you say not happening.
random thought; could have been moisture on it causing a quick short type thing and now all ok as dried out.

 

[Mike FR+]

Yeah but the battery light is still on.

I think I will disconnect the battery for a half hour or so and see if that helps to reset it. If not, I will have to check the fuses and vagcom it.

 

[MJ]

If the battery light is still on you need to check the charge rate of the alternator with a multimeter. Turn everything on (lights, heater blower. heated rear screen etc) then check what power is being produced - it should be 14.5 volts (or there about).

The battery light usually signifies none charging. Usually the diode pack (a diode is a one way electrical valve) has failled and is letting the current flow backwards thus shorting out and causing the light to come on.

 

[Mike FR+]

Bit of an update. Car started when I got in, I turned everything on then the TCS, ABS and airbag lights all came on. Stopped the car and it wouldnt restart. I left it a few minutes and it started with a struggle. The battery is obviously drained.

I dont know if this is cos of the alternator or another reason???

I think it may be the alternator.

Can anyone talk me through how to change an alternator? I did one on my saphire cosworth, but that was a long time ago now.

 

[Mike FR+]

Right, had the alternator tested and it is knackered, was reading 10.4v when tested.

Does anyone know where I can get a cheap alternator?

 

[oldman]

seremotors on here are good from what i have read.
cheap and quick delivery

 

[ToledoNorthEat]

Right, had the alternator tested and it is knackered, was reading 10.4v when tested.

Does anyone know where I can get a cheap alternator?

Found one for £55 inc postage...? (2nd hand)

 

[GrahameS]

Right, had the alternator tested and it is knackered, was reading 10.4v when tested.

Does anyone know where I can get a cheap alternator?

Was going to say - Alternator.. That's exactly what happened to mine.

Fortunately it was 2 days before my warranty ran out, so got it fixed for free

 

[SimonFRTDI]

Similar thing happened to me, turned out to be a bad connection in the fuse box from the alternator. Fried the whole thing and it was replaced under warranty. Sparks etc had melted some of the fuse box cover!

 

[Mike FR+]

Well thats me £170 lighter lol. New alternator, labour and had 4 wheel lazer alignment as I invested in some Falken FK452's.

Not a bad price I suppose

 

[oldman]

all in that's quite good really.
at least all sorted for the nice warm weather

 

[Mike FR+]

Yeah, all fixed for the extra 8 inches of snow we have just got lol.
Mine is **** in this weatrher too, have to drive the wifes Range Rover

 

[MJ]

have to drive the wifes Range Rover

You flash git