cameltrophyallroad

Looking for some direction here: brand new battery, car sat at airport 9 days then battery was dead. All dome lights were manually switched off and alarm was set with doors locked. The date/time is now off by one day, leading me to conclude the battery held on for 8 days before becoming completely spent. I have a Fluke meter and want to check if the draw happens when the doors are not locked/alarm not set. LCD cluster accurately shows doors and trunk opened/closed, the trunk hatch light however stays on all the time so i unplugged it before leaving car for 9 days.

VAG codes are:
01366 opened due to crash signal
35-00 --
01565 Luggage compartment light (w3)
29-10 short to ground - intermittent
00668 supply voltage terminal 30
07-10 Signal too low - intermittent
01561 Rear left door
59-10 Can't Unlock- intermittent
01366 opened due to crash signal
29-10 short to ground - intermittent
00951 Tailgate central locking motor relay (J398)
29-10 short to ground - intermittent

Going to inspect wires in boot between trunk hatch and car next, wondering if the Central Locking module could be losing its mind as well, the 01366 is proving to be elusive.
thanks

5v/cyl

Hook up the meter to get a baseline amp draw and then start pulling fuses one at a time and watch the effect on the amp draw. Once you find the problem circuit you will see a change in the amp draw. Now you've narrowed it down and can start looking for specific problems with the high draw circuit.

dieselrules

you can select the current range on the FLUKE DMM by choosing where to plug in the RED + Lead.
I think the high-current is 10A, low is ??? 300 mA

You need about 3 or 4 hands, but:
loosen your positive battery terminal
put the meter into current mode (suggest 10A to start)
Put the meter + on the + battery POST
Put the meter - on the + battery terminal
Current will be zero because they're still connected.
Lift the terminal off the battery.
Once they are separated, the current will flow through the meter instead of direct.
Check the reading. It should be low.
IF it is lower than the max-current of the low range, then you want to check on the low-range, because its more accurate on low current
So .. Put the terminal (cable) back on the post.
Meter can be removed, + lead moved to low-current connection, then put it back in the system and repeat the above sequence.

We build computers that go into heavy utility trucks, and also light vehicles.
General rule-of-thumb in the aftermarket auto electronics world is that the MAX draw when everything is "OFF" should be 10 mA.
That will take weeks, more than a month, to drain a battery that's in good shape.

If the current is > 10 mA then you have a problem.
But you still don't know what the problem is.

However, you have the tools. You can start playing with devices, disconnecting one-at-a-time, to see what disconnection drops the load.

HINT: How to cheat at this game: Go for the fuse panel. While watching the meter (you need 4 eyes too!) remove fuses one-at-a-time.
When you pull a fuse and the current drops, you've found the problem.

Good luck!

cameltrophyallroad

thanks, i'll start working on that

cameltrophyallroad

So i went through this process and got it to pass through the 10A setting no problem which gave me a reading of 0.07. i could not get it to pass through at all on the 400Ma setting. for reference i checked car # 2 which has no problem with the battery dying and it was about the same; 0.07. Assuming i'm using the Fluke correctly, this all leads me to believe there was something triggering the alarm or the likes. I did find and repair some cracked wires going to the trunk latch/light. still getting the open due to crash signal which is like unrelated, but the alarm in general is not working. it locks and unlocks the car but it does not go off if a door is opened.