Flat battery on daily driver.

[chiefmechanic]

My daily driver is a 1998 a4 b5 Tdi Quattro saloon. It has 136,345 miles atm. My problem is that the battery goes flat overnight. Can anyone tell me how to check for whatever is draining the battery. I have tried a different battery and the same thing happens. Vcds shows no faults. All help welcome. Brian

[caterpillar]

classik.. the stereo. or the amp.. or... the generator regulator( the brushunit)....

[chiefmechanic]

Flat battery

Thanks. Generator disconnected already so not it. Radio next. Brian

[mdz]

One way to find what's draining your battery is using a multimeter set to measure amperes (usually 10A). Disconnect positive battery lead and connect multimeter there in series. Normally it should read between 0.03A and 0.05A. If it reads higher, then there's drain. Pull out fuses one by one and check when reading drops. Usually all aftermarket stuff like alarms, amplifiers e.t.c. has their own fuses in them or in their wiring.
BTW Alpine headunits tends to drain battery if front panel is not removed.

[bluequattro]

Lights in grab handles?
That's what flatten my battery in no time

[domas]

+1 for mdz's post
my becker headunit would drain if not wired properly.

[chiefmechanic]

Flat battery

Thanks for the replies. Radio disconnected and still has a drain. Back to the grindstone. Brian.

[domas]

just unplug the fuses. one at a time

[chiefmechanic]

Battery drain

Went out this morning and it started. Will try again tomorrow but an intermittent fault is the worst kind to have.