Audi TT 3.2 - Battery losing charge

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Tue 9 Sep 2014 13:15
Audi TT 3.2 - Battery losing charge - ChrisGT

Hi, the battery on my Audi TT is losing its charge. I have replaced battery but problem remains. I am charging it everyday driving 5 miles to work and battery is flat again at the end of the day.

Car is 2004 (first model) with 60k miles.

Can anyone suggest what problem may be?

Thanks in advance!

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Tue 9 Sep 2014 13:41
Audi TT 3.2 - Battery losing charge - skidpan

Its either the alternator or there is a current leak on an electrical component that is discharging the battery whilst its stationary.

Easy to check charge rate, digital voltmeter across battery terminals, with the engine at idle should be at least 14.2 volts, probably be nearer 14.4 volts.

Other than that you need an auto electrician.

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Tue 9 Sep 2014 14:29
Audi TT 3.2 - Battery losing charge - gordonbennet

Eliminate the obvious first, turn the interior lights completely off and remove any boot underbonnet and puddle light bulbs.

An ammeter temporarily linked between a battery terminal and its connection should give you a figure to work with, if you leave the ammeter connected you could disconnect fuses in turn and hopefully find one that stops the discharge, there wil be minor current running anyway with such things as alarms etc running but these things should use tiny currents.

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Tue 9 Sep 2014 14:50
Audi TT 3.2 - Battery losing charge - ChrisGT

Thanks skidpan, gordonbennet!

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Tue 9 Sep 2014 14:57
Audi TT 3.2 - Battery losing charge - gordonbennet

Don't leave Chris, a polite poster is always welcome..:-)

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Tue 9 Sep 2014 15:10
Audi TT 3.2 - Battery losing charge - Sulphur Man

Any after-market accessories fitted? eg. Parrott bluetooth kit, or phone charging cradle?

In five years of ownership the only issue with our Honda FR-V was a sporadically depleting battering caused by a Parrot bluetooth handsfree kit.

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Tue 9 Sep 2014 16:48
Audi TT 3.2 - Battery losing charge - gordonbennet

Check sunvisor mirror lights, if fitted, one of those caused a flat battery for us once.

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Tue 9 Sep 2014 19:07
Audi TT 3.2 - Battery losing charge - madf

The classic cause: a bootlight staying on when the boot is closed.

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If you cover no more than 100 miles per day and have easy access to a charging point at home or work, then an EV is ideal for you.

Is an electric car right for me?