Could someone please post a step-by-step guide to diagnosing battery drain? I've seen several posts along the lines of "put an ammeter in line with each fused circuit", but since I have no experience of doing this (and as yet, no ammeter) I could use some more detailed instructions :-)

Why do I deserve help/sympathy? Read on...

I bought my TT new in 2000, and it was absolutely fine for the first year or so, but then suddenly started draining the battery if it wasn't driven for a few days. That got worse and worse, and now it can barely last overnight.

I keep it on a top-up charger, in a lock-up garage that I rented specifically for this purpose, and since that garage is quite a distance from my house, I haven't actually driven more than about 1,000 miles in the last 2 years. :-( It's costing me a fortune to garage a car that I can't drive!

Naturally since the problem first occured while the car was under warranty, I did take it in to the dealership for repair. The first time, they simply replaced the battery and gave me it back. With a nice fresh battery and occasional driving, it lasted a couple of weeks...

Second time, I obviously had to charge the battery before I could take it back to the dealer. They had it for a week, and said they could find nothing wrong with it because it started first time every day. I don't think they'd done anything more than that. I left in disgust - but have since regretted that, since it's now no longer under warranty!

Note: my instrument cluster did go bad at one point (it was flashing and flipping the guages all over the place), and that was replaced under warranty. I can't remember whether that was before or after it first started draining the battery - I think it was before, but not immediately before.

I also have another problem now - the turn signals would work only for a short time - now they don't work at all. From reading this forum it sounds like it's the turn signal relay that's died. I'll get this replaced, but I don't think this is the cause of the battery drain, since the turn signal has only been a problem for the last couple of months.

 

at Radio Shack or other places. You really don't need anything expensive. You would then remove a fuse and put the ammeter connected in it's place. One lead on one end and one lead on the other. The ammeter actually replaces the fuse and any current in the circuit will flow through the ammeter and show the actual current flowing. You would need to do that with each suspected circuit. Each circuit should be next to nothing. You can also disconnect one of the battery cables and put your ammeter in series, one lead to the empty battery lead and the other on the removed battery connection. This will show you the overall current draw with the ignition off. Again it should be next to nothing. The only circuits that may draw a minimal amount of curent would possibly be the radio, alarm circuit and ECU circuit.