Drain on battery

Jet2004uk

Registered User
Joined
Sep 26, 2013
Messages
423
Reaction score
87
Points
28
Location
Lincolnshire & Stockport
hi guys

Have had one or two little issues, last few days leaving home lights stopped working (coming home work fine) odd occasion engine turn over / start slightly longer than normal, finally (which may answer previous issues) left car for two days went to it and battery was completely dead, greenflag came and boosted it no problem, so went into my local garage today to get battery tested, turns out battery is fine but I have a constant draw of 0.6 amps, they dont have the gear to trace where it maybe coming from so just wondering if the likes of VCDS would locate the problem? or has anyone got any idea what it might be the cause of the drain, something not shutting down or turning off ?, have checked obvious things like interior lights and glovebox

any ideas most welcome

Cheers
 
You need a circuit current tester or multimeter, to check what fuse has the draw then eliminate the systems from this.

Do you have an rns, bt or fiscon unit fitted?
 
Just a thought. Have you checked that the radio is off? Sometimes the volume is turned down so far that we think it is off. The only other way, would be to pull fuses while monitoring the battery drain. Did you check the boot light? What you have is a 7.2Watt sink which does sound a bit like a lamp. Good luck.
 
coincidence NHN I recently fitted a new head unit couple of weeks ago, Zenec purposely made for the A3 (was a straight swap) my garage have asked me to remove it and they will retest to see if its still drawing just incase it was the new head unit
 
Thanks Westy, is there any kind of problem pulling fuses from a canbus sytem with the ignition off? as my local garage is opposed to the idea, I trust this garage 100% been going to it since I was 18 am now a young 41 so I have no reason to argue with them they do admit they not fully kitted up for this type of vehicle, so does anyone know of any issues with this kind of check on a canbus system?

Thanks
 
As long as the ignition is off you will be ok. May have to input the radio code and reset the clocks but that's it.
 
  • Like
Reactions: Westy
As long as the ignition is off you will be ok. May have to input the radio code and reset the clocks but that's it.
 
Cheers, seems a good and cheap way to narrow it down, does anyone know if VCDS would locate this type of problem? as I was planning on actually buying VCDS
 
Unfortunately not. VCDS is unable to measure amperage drain on the battery.

As Westy linked to, a proper Voltmeter needs to be used. These can be bought cheaply via Maplins, B&Q etc.

Also can a mod delete my double post if they see this. ****** phone.
 
Update:

Turned out it was the new Zenec head unit I installed, even though it was a straight swap with no modifications to wiring the unit is pulling 0.6 amp when powered off, I have been in touch with Zenec who asked me to do various updates (CANbus) they said this would solve the problem of power drain, even with the CANbus update done it is still drawing the 0.06 amps, will see what Zenec say but looks like I will be sending the unit back
 
Are sure the unit is faulty? According to the above video there should be some draw out of the battery. 0.06 doesn't seem alot of drainage. ..
 
My RNS-E used to drain my battery until I moved the Bose PIN to the correct location, and coded the RNS-E correctly.
The battery used to drain if the car was not used for 3 days or so, now it lasts a lot longer, although if I know I am not using my car for over a week I'll pull engine bay fuse 19.

I was originally getting 3.8 amps on a draw test.
Pulled fuse 19 in the engine bay and was getting 1.4-1.6 amps
Now I draw 1.4 amps after sorting out what I mentioned above.
 
Going to do the test in the morning. I still thinking its a faulty battery as its just come on sudden. I went away last month for a week and came back and the car was fine. Didn't use the car at the weekend but when i came back to it its dead!!
 

Similar threads

Replies
20
Views
3K
Replies
0
Views
780
Replies
4
Views
1K
NHN
Replies
16
Views
5K