2002 Audi A4 Battery or Altenator?

bob2oo7

Hi guys

Just looking for some assistance please to determine if my battery is dying or there is a problem with my alternator

2002 Audi A4

Battery was replaced 4/5 years ago but I cant remember if the symptoms were the same.

Friday night, car was fine, no problem

Saturday morning when I went to start the car it took a good 20 seconds to turn over, when it did, the clock/date reset it itself and I get a RED Brake warning light flashing and beeping for a few seconds and the ESP light stays in for a couple of mins

After driving for a bit the car turns over with out any issues, but the longer I leave it off, the longer it takes to turn over

I read somewhere to start the car, and disconnect the Negative cable on the battery, if the car stays on, then its the battery, if it goes off then its the alternator

Any thoughts?

Thanks in advance

Philip82

Get a voltmeter and test the current in your battery with the car switched off. It should average around 12v dc. Then start the car and test again, this time it should read around 13 or 14v. If its reading any less than this I would be assuming its your altenator. If your under 11volts with the car turned off its your battery. P.s if you have a battery charger it might be worth sticking it on a charge.

bob2oo7

If I cant get a Volt Meter, is there any other way?

Bigus

Most likely it's the battery going on experience, and the fact it's 4-5 years old.

Philip82

Any diy store, auto store or electrical wholesale would have one, they are not expensive and a great addition to your tool kit.