2.0 draining battery

[volvofh]

:confused: hi my friends sister has a 2007 2.0 petrol tt an she is havind problems with it.the car just out of warranty. when she goes out to the car to go to work,when she tries to open the car the battery doesnt have enough power to open the central locking.after putting the jump leads on the car opens an starts ok.after fitting a new battery to the car it would run ok for a while then it would happen again.the battery wolud be completely dead.has anyone any ideas why this is happening?:1zhelp:

[Zenerdiode]

It could be:


Bad Battery
Bad Alternator
Current Drain

First thing to do is give the battery a good overnight trickle charge. Even for a new battery, you don't know its actual charge level when you get it. I don't know if the battery has a Condition Monitor like on the latest A4's but check the user manual under 'Battery Charging' because it may advise to connect the charger in a different place than the battery posts.

Start the car and let it idle. Measure the voltage across the battery posts. It should be at least 13.8V but no higher than about 14.5V - if within that range; the alternator is good.

Over the next few days, if the battery gets run down again, it is either a current drain or another bad battery. There are a few different ways of checking for a current drain - I prefer a non-intrusive method of using a hall-effect clamp meter around the battery negative lead. A direct method is to connect the ammeter between the battery negative post and the battery negative lead. You need to fool the car it's fully locked so close the bonnet catches and any doors that are open and lock the car. When locked with the fob, all the systems in the car should shut down in about 10-20 minutes and the remaining current draw should be the alarm/central locking system - I'd expect the current draw to be in the order of a few tens of milliamps. Any more and there is something draining the battery.

[volvofh]

ok i will check these out first to see.thanks for the help.:approve: