Battery drain

[Guest]

Hey, 

im having a battery drain issue, done checks with a multimeter today & found a 6.90/7.08 amp drain. I think I’ve narrowed it down to the central locking/alarm system, I’ve found if I lock with the fob the drain stays at 6+ amps but when locked manually with the key the drain drops to 0.14. I also have issues with the doors not opening from the outside & will need to be opened the inside first and then they’re fine until I lock the vehicle again! This mostly happens in the winter and seems to self resolve in the summer. Has anyone experienced any similar issues? 

[Stevey Y]

1 hour ago, Charlie1280 said:

Hey, 

im having a battery drain issue, done checks with a multimeter today & found a 6.90/7.08 amp drain. I think I’ve narrowed it down to the central locking/alarm system, I’ve found if I lock with the fob the drain stays at 6+ amps but when locked manually with the key the drain drops to 0.14. I also have issues with the doors not opening from the outside & will need to be opened the inside first and then they’re fine until I lock the vehicle again! This mostly happens in the winter and seems to self resolve in the summer. Has anyone experienced any similar issues? 

Hi good skills but I think you should get the car plugged in that will give you a definitive code for the part that is running to ground, possible broken cables  where the door loom plugs  meet the body or a control module failing, my guess is a plug connector somewhere is corroded as I doesn't seem to occur in drier weather which would suggest cold and damp getting in somewhere.

Steve.

[Magnet]

Hello Charlotte,

When you say you have a c7amp drain when the car is locked with fob, was this test done straight away, or about a minute after it is locked? As I understand it, the normal current will drop after that time, once the alarm and immobilisers have set. 
140mA when locked with the key seems high to me. I would have expected more like 50mA once everything has set. 
It sounds as if you you are going to need to invest in an hour or so of an auto electrician’s time. 
Kind regards,

Gareth. 

[Guest]

Tested first while the car was locked pulled every fuse (individually) to check if I could find a drain that way, then realised once locking with the fob the car would have a big drain & as soon as I locked with the key this drain would drop after a minute. Spent a few hours outside doing tests today and that’s what I found, I’ve currently got it on charge & have locked it manually I will see over the next few days if I’m going out to a dead car or not. 

I’ve added some pictures of the readings I was getting before (locked with fob) & after locking manually with the key. Almost instantly a huge difference.

 

[Magnet]

Ok, but I’m still not sure if your 7 amps was measured immediately it was locked with the fob rather than 1 minute later- your write up suggests straight away, but it’s unclear. 

Could you please clarify. 
Kind regards,

Gareth. 

[Guest]

I had the car locked with the fob while I was investigating the fuses so yes pretty much immediately, however the car was locked for over half an hour while I was testing fuses in the boot & amps was at 06.90 the whole time, then was unlocked while I checked other fuses inside the dash locked again while I stood at the boot racking my brains for a good 15 mins, I then unlocked & locked with the key and within a minute the Amps dropped to the 00.14. I hope that is clearer for you car was sat locked with fob for over 30 mins and sat at 6+amps until I locked with the key. 

[Magnet]

Thanks Charlotte, we are now getting the detail. As I see it, we now understand that you are monitoring the ‘parasitic drain’ with the bonnet open, so there is a strong possibility that the alarm has not fully set (bonnet open) and the system has not gone to sleep. 
If it were mine, I would be making myself a set of well insulated ‘fly’ leads which you carefully feed to the outside of the car, connect your meter to these, then close the bonnet. Wait at least a minute and measure the drain at that point.

Perhaps you could do that and report back. 
Kind regards,

Gareth. 

[Guest]

The battery is in the boot, and I had closed the boot off ( so the car thought the boot was shut) so it was defiantly shut down. Readings were accurate and also took advise from an auto mechanic.  

 

[Guest]

Plus I know the alarm was on because I kept setting it off. 
 

Charlie 

[Magnet]

Thanks.

‘ (so the car thought the boot was shut)’- ? 

Anyway, if (I’ll avoid the caps) the car is fully shut down, and you still have at least a 140mA drain, then that is c x3 too much, so all I could confirm is that yes you do have an issue.

What that issue is, is obviously going to need on-car investigation as apposed to distance-diagnosing, so apologies, but I cannot help you further. 
Perhaps someone else on here may.

It sounds as if you are now going to have to invest in an hour’s services of your friendly auto electrician. 
Perhaps you’d like to let us know how you get on. 
Kind regards,

Gareth. 

 

[Guest]

Come out to it this morning and it’s dead again, I had it on charge all day yesterday pretty much & drove it last night. 

[Guest]

I’m going to book it in with an auto electrician Monday and see what he can find I’m hoping it’s not going to be too costly. 
 

will keep you updated. 
 

Charlie. 

[Magnet]

Sounds good. 
If 7 amp drain then in 12 hours (84Ah) it will of course be completely dead. 
Pending getting the car inspected etc, why not disconnect it overnight/ when not in use? OK it may mean you have to recode the radio etc., but better than having to keep recharging the battery. 
Kind regards,

Gareth. 

[Magnet]

Hello Charlotte again,

Having given this a couple more coats of thinking about, and revisiting your initial post, you may find the following to be of some help:-

7amp equates to 84 watts ( compare a headlight bulb of say 65w) and I would consider this to be a far more than that necessary to drive an alarm and immobiliser set up. So we could be looking at a partial short situation here. 
 

Your post mentions this is worse during winter months, so what happens then? Wires become less flexible in cold weather and continual flexing can lead to breaks/partial breaks, and if this occurs, then individual wires can short against one another. The favourite spot is within the flexible harness which links the body with the boot and this would be my first port of call. You will need to release the rubber over over at one end and pull the cover back to reveal the individual wires - checking for full or partial breaks. If all is well in the body to boot area, then it’s worth looking at the similar link from the A post to the driver door. 
Perhaps you could let us know the outcome of these inspections.

Kind regards,

Gareth. 

[Guest]

Hey, 

quick update, I had a diagnostic test done today and looks like it’s my comfort control module along with some possible breaks in my wiring. Think it’s a job for main dealer unfortunately as if it’s the CCM it will require re programming to the car, it’s going to get expensive 😢

I’ve attached a picture of what come out on the reader, if anyone can make anymore sense from the codes let me know.

charlie. 

[Stevey Y]

Hi sound like a corroded terminal on the electrical control module the data bus can't connect to the module to interrogate  the module, try and find someone with VCDS/VAGCOM diagnostics as this will give the part number of the module and the long coding for the module so if you get another unit it can be coded to the car fairly easily, no need to go anywhere near a main dealer try and find a garage that does VAG vehicles

Steve.

[Guest]

I am struggling to find anyone in my area that knows anything about these sorts of issues. Audi are quoting me just over £150 for a 45 mins investigation plus another £500 odd for the module. I feel like I’m way in over my head. 

[Guest]

25 minutes ago, Stevey Y said:

Hi sound like a corroded terminal on the electrical control module the data bus can't connect to the module to interrogate  the module, try and find someone with VCDS/VAGCOM diagnostics as this will give the part number of the module and the long coding for the module so if you get another unit it can be coded to the car fairly easily, no need to go anywhere near a main dealer try and find a garage that does VAG vehicles

Steve.

Any idea what the open circuit means and I’m assuming this all makes sense to why my doors don’t open as also chucked out codes for each of them to. 

[Stagn8]

An open circuit means a break in the circuit somewhere, as you mentioned, a broken wire would do it, just means voltage or current can’t travel past the break so nothing reaches whatever is being actuated so it doesn’t work. It would certainly be a probable cause of the actuators/ solenoids in your doors not working. Equally it could be switches not working, modules not outputting, all sorts in fact, so take Steven Ys advice and get it scanned for the correct module number, cheaper in the long run.

[Guest]

12 minutes ago, Stagn8 said:

An open circuit means a break in the circuit somewhere, as you mentioned, a broken wire would do it, just means voltage or current can’t travel past the break so nothing reaches whatever is being actuated so it doesn’t work. It would certainly be a probable cause of the actuators/ solenoids in your doors not working. Equally it could be switches not working, modules not outputting, all sorts in fact, so take Steven Ys advice and get it scanned for the correct module number, cheaper in the long run.

Okay I did think that meant a break somewhere, I have tried looking online for specialist in my area but I’m not having much luck & auto electricians are also hard to come by. I did find one but he’s a fair way away from me and with the car draining so quickly I don’t fancy getting stuck in the middle of nowhere, I’ll have to have another ring around and ask people if they can do that specific scan Steve mentioned.  
 

thank you, 

Charlie. 

[Stevey Y]

32 minutes ago, Charlie1280 said:

I am struggling to find anyone in my area that knows anything about these sorts of issues. Audi are quoting me just over £150 for a 45 mins investigation plus another £500 odd for the module. I feel like I’m way in over my head. 

Hi try and google in VAG specialists your area they are much cheaper than Audi

[Guest]

I’ve had a so called mechanic message me, I asked him if he can do a VCDS/VAGCOM diagnostics as Steve stated & this was his reply, can someone please translate for me lol 😂 I don’t wanna get ripped off.

“We have dimsport, autel, snap on equipment we’ve done many ecu codes, immo codes, ccu, abs bcms but if you don’t want to go down that route I guess Audi is going to be a option for you?” 

[Guest]

Had a vag specialist out today, he’s told me I have the wrong battery & the wrong alternator on my car & that it’s only charging at just over 12v, he’s also saying it’s a start-stop car which I wasn’t aware of? He’s quoted nearly £500 to change the battery & alternator (I had the alternator changed last week!) but I know that changing these parts isn’t going to stop the 7amp drain on my battery. 

[Magnet]

Hello Charlotte, 

Wrong battery = your current battery is not an AGM type which is the norm for the stop/start function vehicles. This battery type requires the ‘intelligent charging’ alternator, and if you don’t have the correct one then it will wreck the correct battery and vice versa. 
How long have you had the car?
Just wonder if someone had swopped the battery before sale, and then the original alternator gives issues because it’s dealing with charging an incorrect battery type - and that maybe where you came in! 
I think the parasitic drain may well be an additional issue, but it may be sorted via. fitting the correct battery and alternator. 
Note:- the battery ( and alternator?) may well have to be coded to the car when it is fitted. 
Wonder what your plan is now with the car Charlotte.? 
Kind regards,

Gareth. 

[Guest]

I rang Audi and they confirmed my car isn’t a stop/start it’s a 58 plate. I’m unsure what to do with the car I can’t seem to find anyone to fix it, going to try get the door panels off at some point and see if changing the actuators help with the drain if that fails them I’m stuck.