Flat battery but why?

[Fossil]

I've bought a brand new battery but went to start it today and it's flat. Something is draining my battery very quick. I haven't had it going for a few days. All I connected to it was a in car dash style tv stereo. One of those cheapie of ebay. However, there is some kind of box connected to the positive and running somewhere. It does have a rear air conditioner that I don't want. Could this be powering that? Could somebody please tell me what should be connected from my positive and negative terminals. I just want it stock standard. Any ideas how I can take it back to that please? Here is a connection similar to mine. What's that black box connected to the positive terminal with the thick red wire for as I have one as well? I just want stock standard so can I get rid of this box?

[Umai Naa!!]

That box looks standard. I'd probably leave it as is.

Perhaps unplug the new stereo and see if that's what's causing it. You need to be very sure you've wired it up correctly, because IGN OFF, is not IGN OFF until you pull the key out.

[Fossil]

That box looks standard. I'd probably leave it as is.

Perhaps unplug the new stereo and see if that's what's causing it. You need to be very sure you've wired it up correctly, because IGN OFF, is not IGN OFF until you pull the key out.

thanks. I was working in it today and had the key in the ignition all day. I did turn off the interior lights but that was all. Still don't understand what that black box is for though?

[Gold Coaster]

Not sure what's what there but if you have a multimeter you might be able to trace the drain. There's lots of help on Youtube such as How To Perform a Parasitic Draw Test - EricTheCarGuy - YouTube

[Umai Naa!!]

If you pop the cover off, it'll be full of fusible links to everything in the van.

[Fossil]

If you pop the cover off, it'll be full of fusible links to everything in the van.

any ideas on what they may be though?

[Umai Naa!!]

Usually for things like the fans, alternator, that sort of thing.

[Fossil]

Usually for things like the fans, alternator, that sort of thing.

Okay. I'll havet to jumpstart it in the morning and take it for a drive. An hour should bring it back up to full charge I reckon. Any precautions when jumpstarting I need to know about as I'm very new to veedub? I appreciate all your help. I will get a multimeter on Thursday and do some tests to see what the big drains are.

[Sunny43.5]

AS Umai says the stereo could be the culprit , I have found some of those on Ebay have wiring which is all over the place .Many years ago I had to unplug several wires from the supplied connector because they were in the wrong holes . The diagram in the booklet said one thing and the label on the back of the unit had it another way . What year van ?

[Fossil]

AS Umai says the stereo could be the culprit , I have found some of those on Ebay have wiring which is all over the place .Many years ago I had to unplug several wires from the supplied connector because they were in the wrong holes . The diagram in the booklet said one thing and the label on the back of the unit had it another way . What year van ?

It's a 2002 T4 2.5 TDI