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Audi A3 1.9 TDi 2005 - Parasitic drain - Fixed #

Posted by Mark Robins on March 20, 2015, 1:34 pm

Year of Manufacture *: 2005
( Optional ) Engine Code or CC: 1.9 TDI

Hi Gents,

Pulling my hair out (if I had some)! Have this 800 milliamp drain on the battery after modules have all gone to sleep. Traced it to the main fuse bus F6 which AD says supplies the fascia fuse box, pulled all the fuses drain still there, disconnected the following...

Fuse box relay plate in dash, convenience unit, ign switch, instrument panel, I notice that the hazard warning lamp stays illuminated but can find scarce info from elsa-win and AD about it

Anyone got a silver bullet?

Mark

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by Mark Robins <iframe src='https://members4.boardhost.com/ukautotalk/info/user=ukat3563' width='330' height='300' border=0 style='border:none;'> on March 20, 2015, 2:25 pm, in reply to "Audi A3 1.9 TDi 2005 - Parasitic drain #"
Mark Robins

Forgot to say, also checked vanity lamps on visors, boot lamp, glove box lamp/

Mark

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by Ian Baxter <iframe src='https://members4.boardhost.com/ukautotalk/info/user=UKAT1560' width='330' height='300' border=0 style='border:none;'> on March 20, 2015, 3:36 pm, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"
Ian Baxter

Hello Mark,
No silver bullet, But does it have a bonnet catch switch ?

Ian.

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by Mark Robins <iframe src='https://members4.boardhost.com/ukautotalk/info/user=ukat3563' width='330' height='300' border=0 style='border:none;'> on March 20, 2015, 5:15 pm, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"
Mark Robins

Yes it does, good point I'll check it and come back.

Mark

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by Mark Robins <iframe src='https://members4.boardhost.com/ukautotalk/info/user=ukat3563' width='330' height='300' border=0 style='border:none;'> on March 20, 2015, 6:52 pm, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"
Mark Robins

Bonnet switch is working Ok, bonnet open warning comes on in the dashboard and goes out when closed. 3 Hrs in nothing to show for it so far, probably going to be something stupid and I'll wonder why I didn't think of it first!

Mark

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by Mark Carter <iframe src='https://members4.boardhost.com/ukautotalk/info/user=UKAT1428' width='330' height='300' border=0 style='border:none;'> on March 20, 2015, 7:48 pm, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"
Mark Carter

Forget AD, its time to get erwin or even the older ELSA on the boil and see what that fuse really supplies

Mark

Modern cars, Its all wizardry and witchcraft

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by andyhyoung <iframe src='https://members4.boardhost.com/ukautotalk/info/user=UKAT5148' width='330' height='300' border=0 style='border:none;'> on March 20, 2015, 8:47 pm, in reply to "Audi A3 1.9 TDi 2005 - Parasitic drain #"

I think if this were my job ,I would be looking at a different approach.Firstly make sure you are starting with a fully charged battery,as a low voltage can cause various controllers to throw a wobbly.Carry out a global scan of all controllers to see if there any relevant fault codes .Disconnecting consumers and pulling fuses is counter productive,as vehicles using can network need a power supply to switch off.Use an amp clamp that is capable of accurate low current readings so that wires carrying power can be isolated without cutting/intrusion.You can pick out wires from behind the fuse box to see which is drawing power.Also may be an idea to get an "amp hound" which can check power draw across the back of a fuse.Also and non standard equipt fitted?
http://public.snapon.com/a_prodannouncements_us/EECT74_NPA.pdf

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by Chris Fox <iframe src='https://members4.boardhost.com/ukautotalk/info/user=ukat3793' width='330' height='300' border=0 style='border:none;'> on March 21, 2015, 12:39 am, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"
Chris Fox

If the hazard light switch is staying back light, that's telling you that the CAN network is still awake.

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by Mark Robins <iframe src='https://members4.boardhost.com/ukautotalk/info/user=ukat3563' width='330' height='300' border=0 style='border:none;'> on March 21, 2015, 9:25 am, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"
Mark Robins

Thanks for the response Gents,
Been to Elsawin and they don't have the current flow charts for the car in question, vehicle battery is being maintained and charged with C-Tek charger and I am using Picoscope with amp clamp for testing, point taken on disconnecting modules, I noticed that by pulling the plug on the headlamp switch the lights come on! If the network is staying "awake" why is only the hazard warning lamp illumination staying on? Did try clamping cables on the fuse box but it's pretty tight, But will try again to isolate where the drain is by clamping cables on the back of the interior fuse-box.

Mark.

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by Tony Sefton <iframe src='https://members4.boardhost.com/ukautotalk/info/user=UKAT5581' width='330' height='300' border=0 style='border:none;'> on March 21, 2015, 9:49 am, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"

One of my staff struggled with a VW when looking for a battery drain, He used to leave the doors wide open but with the catches closed so that it thought the doors were shut, he used a digital multimeter connected in series with the battery negative lead. ( We never moved on to scopes for this procedure )

He spent hours trying to find the drain and kept checking and rechecking but could never find the drain, He then opened and closed the doors and locked it up and went for lunch and within a few minutes the vehicle had gone to sleep.

So, rather than just making sure that the doors are latched, If the ignition has been turned on and off, Make sure that you open and close a door.

I am not sure how long it takes them to go to sleep without opening and closing a door but it was a long time and it can catch you out when you are working between jobs, pulling fuses and trying to find a fault in a reasonable amount of time.

H.T.H Tony.

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by Mark Robins <iframe src='https://members4.boardhost.com/ukautotalk/info/user=ukat3563' width='330' height='300' border=0 style='border:none;'> on March 21, 2015, 9:57 am, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"
Mark Robins

Thanks Tony, I close all the door locks, bonnet catch while keeping the doors open for obvious access reasons, I have read on this forum about a tracker being installed and causing a problem, but so far I can't find and after market devices plumbed in anywhere. I have to see if I can narrow down my search by clamping the interior fuse box as has been suggested.

Mark

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by Jim Power <iframe src='https://members4.boardhost.com/ukautotalk/info/user=ukat3202' width='330' height='300' border=0 style='border:none;'> on March 21, 2015, 11:55 am, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"
James Power

Hi Mark

Probably not your problem but,

I had a Mk 5 golf with a parasitic drain caused by the owners small child putting 2 cd's in the player. The player was trying to eject but unable to do so and this kept the bcm awake.

Jim.

jim power

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by Mark Robins <iframe src='https://members4.boardhost.com/ukautotalk/info/user=ukat3563' width='330' height='300' border=0 style='border:none;'> on March 21, 2015, 2:00 pm, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"
Mark Robins

The plot thickens,
Took the interior fuse box out stripped back insulation to get on the individual wires. I can see the main feed wire which is the same thickness as the wire on the main bus fuse and clamping it I got a figure of 200 milliamps which from previous experience I think is correct, so that eliminates all consumers on the interior fuse box (for good measure I did go through all the cables as well) Of course the mystery is where is the 600 milliamps going. Some where between the bus fuse and the interior I have a drain.
I checked out the snappy tool and I thought how is this checking amp draw across a fuse? My guess is it's looking at small voltage drops across the fuse blade, so I ran a little experiment. Using a digital volt meter (auto ranging)I checked a fuse with no draw and had exactly 0v registered, with a consumer switched on the same fuse registered 0.02v, basically if there is any v reading then that fuse is drawing current. Biggest problem is the mini fuses very often don't have the terminals exposed.
Sorry for the long post and thanks to everyone's input.

Mark

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by aidan birley <iframe src='https://members4.boardhost.com/ukautotalk/info/user=UKAT2879' width='330' height='300' border=0 style='border:none;'> on March 21, 2015, 2:48 pm, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"
Aidan Birley

Hi

This link may help

http://info.powerprobe.com/fusechartsdownload

cheers aidan

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by Mark Carter <iframe src='https://members4.boardhost.com/ukautotalk/info/user=UKAT1428' width='330' height='300' border=0 style='border:none;'> on March 21, 2015, 10:05 pm, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"

The way you are checking for VD across a fuse is the very way that VAG teach their Techs,

There is a chart for the type and rating of each fuse along with the VD and corresponding Amps drawðŸ˜€

Erwin will have the correct wiring diagram for your vehicle.

Has this vehicle got DAB fitted?

Regards
Mark

Modern cars, Its all wizardry and witchcraft

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by Chris Fox <iframe src='https://members4.boardhost.com/ukautotalk/info/user=ukat3793' width='330' height='300' border=0 style='border:none;'> on March 21, 2015, 11:24 pm, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"

They use the back light of the hazard light switch as a easy tell tale indication, they teach you that on training. You need to test each fuse to narrow down your search, good luck.

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by Mark Robins <iframe src='https://members4.boardhost.com/ukautotalk/info/user=ukat3563' width='330' height='300' border=0 style='border:none;'> on March 22, 2015, 9:57 am, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"

Thanks Gents, Mark I have been to Erwin and selected a few manuals but at the moment there is no current flow manual for this vehicle there; and no DAB fitted, my guess is the Golf will be very close so I'll look at that. The picture shows the main feed coming in with a crimp taking other feed off, the only drain here is going to the fuse box and is only 200 milliamps.

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by andyhyoung <iframe src='https://members4.boardhost.com/ukautotalk/info/user=UKAT5148' width='330' height='300' border=0 style='border:none;'> on March 22, 2015, 10:02 am, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"
Andrew Young

Does this car have bluetooth facility?Or is it too early a model for this.

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by Jon Morgan <iframe src='https://members4.boardhost.com/ukautotalk/info/user=ukat3190' width='330' height='300' border=0 style='border:none;'> on March 23, 2015, 2:32 pm, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"

Did you carry out a full diagnostic systems scan before you started?

Any faults logged anywhere that may have given you a pointer in which direction to look?

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by Mark Robins <iframe src='https://members4.boardhost.com/ukautotalk/info/user=ukat3563' width='330' height='300' border=0 style='border:none;'> on March 23, 2015, 4:48 pm, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"
Mark Robins

Ok I went back and re-evaluated my results. Mark you were right the current diagram was available on Erwin, SA6 bus fuse supplies the following...
S37 single fuse for regulator.
SC12-upto-SC17 Interior fuse box.
SC22-upto-sc27 Interior fuse box.
The crimp on the end then takes feeds off to other units.
My 800milli amps I have found is divided between the interior crimp and the under-bonnet fuse box.
200 milliamps for the interior fuse box and small amounts coming off the crimp.
I removed the bus bar off the under bonnet fuse box and using a jumper measured 400 milliamps draw on that fuse box which I'm inclined to say is my main problem.
Volt Dropping the fuses on this fuse box didn't reveal any draws, so it's time to pull the fuse-box.

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by Mark Robins <iframe src='https://members4.boardhost.com/ukautotalk/info/user=ukat3563' width='330' height='300' border=0 style='border:none;'> on March 24, 2015, 2:08 pm, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"
Mark Robins

Can't get the fuse box checked by anybody so going to bite the bullet and replace it, £150 + VAT doesn't sound to bad.

P.S.
Anyone know if VAG COM is OK for coding/configuration if needed on this?

Fixed #

Posted by Mark Robins on March 31, 2015, 10:56 am, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"
Edited by board administrator April 1, 2015, 2:26 pm

Went back to the drawing board with this one, had one fault code that would intermittently appear so decided to check it out.00470: Company Comfort Databus in single wire - open circuit. Looked at the current flow and Canbus diagrams and found it could be a broken wire in the door module the obvious place, so went straight into the O.S.F. door with the pico and the one CAN low signal was corrupted. Cut a long story short, broken wire in door jam keeping can active.

Many thanks to everyone's contribution, the answer was already there just needed to open my eye's!

Re: Audi A3 1.9 TDi 2005 - Parasitic drain #

Posted by Jon Morgan <iframe src='https://members4.boardhost.com/ukautotalk/info/user=ukat3190' width='330' height='300' border=0 style='border:none;'> on April 1, 2015, 11:11 am, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain #"

Good result Mark,

always worth thinking about the DTC's being linked to the parasitic drain.

Re: Fixed #

Posted by Chris Angus on April 1, 2015, 12:51 pm, in reply to "Re: Audi A3 1.9 TDi 2005 - Parasitic drain # FIXED"
Edited by board administrator April 1, 2015, 2:27 pm

Well done with your perseverance Mark, many would have swerved this job, me included

Re: Fixed #

Posted by Tony Sefton <iframe src='https://members4.boardhost.com/ukautotalk/info/user=UKAT5581' width='330' height='300' border=0 style='border:none;'> on April 2, 2015, 8:42 am, in reply to "Re: Fixed #"

ooops, Now I remember, Thats almost the same as One I had last year, Ours turned out to be a faulty drivers door module, Reading up about the fault, It does cause a battery drain but everything can still work in single wire mode.

Knowing that fault code was present would have jogged my memory.

Jon Morgan suggested the right course of action.

>>>> Did you carry out a full diagnostic systems scan before you started?

Any faults logged anywhere that may have given you a pointer in which direction to look? <<<<<

Re: Fixed #

Posted by Mark Robins <iframe src='https://members4.boardhost.com/ukautotalk/info/user=ukat3563' width='330' height='300' border=0 style='border:none;'> on April 2, 2015, 12:32 pm, in reply to "Re: Fixed #"
Mark Robins

Yep I have to eat humble pie on this one, but I did do a full scan recorded the results so that all configs were there; and then erased all fault codes, did a road test and nothing logged so went about my merry way in total disregard to the first results! 60 is just around the corner and I just hope this old dog can still learn new tricks!

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