Sam B

Hi all

First post so be gentle

I currently have a battery drain on my audi a4 b8 1.8T

New battery was fitted 8 months ago and new alternator around same time, recently after around 2 days of being parked its dead and needs a jump to start.

Garage that I normally use said it looks to be the Body Control module but they were unsure, I bought myself a multimeter and have tried for a few days to diagnose with no luck.

After a full charge with a ctek charger, I had a friend scan the car after i tried pulling fuses, clear the log - scanned again, and then scanned again the next day, the behaviour is after locking the car it wakes up again (usually within 5 minutes). I hooked up the multimeter to the battery and found it went to around 50 mA but when the car wakes up by itself its drawing around 3-4Amps. Then it progresses down to negligible and then wakes up again (does this continuously).

I've checked each fuse one at a time to see if any volts are going through the fuse when the car is asleep (have to stop when it wakes up). I had a few show some the convenience electrics fuse on the drivers side 5A fuse, and the AC 10A fuse

I've pushed the locks with my finger to the full lock position so the car thinks its shut, does the car have any pressure switch or anything on the doors? i looked and can see a few rubber moulds but they don't look like sensors or anything?

On the last scan this came up again:

Address 62: Door, Rear Left (J388)

1 Fault Found:
02115 - Locking Unit for Central Locking
008 - Implausible Signal
Freeze Frame:
Fault Status: 01101000
Fault Priority: 3
Fault Frequency: 1
Reset counter: 92
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:52:20

Could this be why the car won't go to sleep?

I've also noticed when my garage changed the battery they didn't bother putting in the correct serial etc, looks like they may have changed a digit or whatever to tell the system a new battery had been put it. Going to change this tomorrow to correct details but this wouldn't cause the car to keep waking up would it?

Any help greatly appreciated, I've looked everywhere in forums and youtube videos for any inspiration but I'm now at a loss.

Below are some more errors from scan, FYI the aircon is completely shot going to get new aircon pump



Address 08: Auto HVAC (J255)

4 Faults Found:
00457 - Control Module for Network (J519)
013 - Check DTC Memory
Freeze Frame:
Fault Status: 01101101
Fault Priority: 6
Fault Frequency: 9
Reset counter: 94
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:41:24

00256 - A/C Pressure/Temperature Sensor (G395)
008 - Implausible Signal
Freeze Frame:
Fault Status: 01101000
Fault Priority: 7
Fault Frequency: 10
Reset counter: 94
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:41:24

Freeze Frame:
Temperature: 19.0°C

00256 - A/C Pressure/Temperature Sensor (G395)
002 - Lower Limit Exceeded
Freeze Frame:
Fault Status: 01100010
Fault Priority: 2
Fault Frequency: 14
Reset counter: 94
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:41:21

Freeze Frame:
Temperature: 19.0°C
Temperature: 36.0°C
Load: 0.0 %
Absolute Pres.: 1.0 bar
RPM: 0 /min
Speed: 0.0 km/h
Current: 0.000 A
Temperature: 28.0°C

01592 - Air Quality Sensor (G238)
004 - No Signal/Communication
Freeze Frame:
Fault Status: 01100100
Fault Priority: 6
Fault Frequency: 13
Reset counter: 94
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:41:37

Freeze Frame:
Temperature: 19.0°C


-------------------------------------------------------------------------------
Address 09: Cent. Elect. (J519)

3 Faults Found:
02095 - Component Protection Active
000 - - - Intermittent
Freeze Frame:
Fault Status: 00100000
Fault Priority: 1
Fault Frequency: 254
Reset counter: 134
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 19:49:00

03020 - Local databus 2
012 - Electrical Fault in Circuit - Intermittent
Freeze Frame:
Fault Status: 01101100
Fault Priority: 2
Fault Frequency: 226
Reset counter: 134
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:41:00

01592 - Air Quality Sensor (G238)
004 - No Signal/Communication - Intermittent
Freeze Frame:
Fault Status: 00100100
Fault Priority: 3
Fault Frequency: 13
Reset counter: 134
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:42:00

jagtoes

1st I would never charge a battery with a 2-3 amp Ctek. They are used to maintain a battery and not to charge it. The installer should have charged the battery to 100% prior to installation and should have reset the battery SW correctly. All of the fault codes could have been caused by a low battery voltage so assuming that the battery is fully charged (12.6 V sitting for an hour) erase the codes and restart the car. See if any come back again . If so then you need to find someone who is familiar with Audi's and let them do the diagnostic's . They would have the latest SW and the correct equipment to diagnose the system.

Sam B

Hi Jagtoes

Thanks for the reply, have already started enquiring with local garage which specializes in Audi/VW as tried for hours last night trying to find the culprit, that first set of low volts codes were after the battery went dead, ctek charger isnt the small 2-3 amp its this one:

CTEK MXS 5.0 Fully Automatic Battery Charger (Charges, Maintains and Reconditions Car and Motorcycle Batteries) 12V, 5 Amp - UK Plug

These are the scans after resetting to clear low volts etc:

-------------------------------------------------------------------------------
Address 08: Auto HVAC (J255) Labels:. 8Tx-820-043-3Z.clb
Part No SW: 8T2 820 043 M HW: 8T2 820 043 M
Component: KLIMA 3 ZONEN H05 0120
Revision: D0000000 Serial number: 0112.03.080330
Coding: 64040000
Shop #: WSC 06325 000 00000
VCID: 3C7D0379BFF0F6AAC1-8068

4 Faults Found:
00457 - Control Module for Network (J519)
013 - Check DTC Memory - Intermittent
Freeze Frame:
Fault Status: 00101101
Fault Priority: 6
Fault Frequency: 1
Reset counter: 132
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:41:24

00256 - A/C Pressure/Temperature Sensor (G395)
008 - Implausible Signal - Intermittent
Freeze Frame:
Fault Status: 00101000
Fault Priority: 7
Fault Frequency: 1
Reset counter: 132
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:41:24

Freeze Frame:
Temperature: 19.0°C

00256 - A/C Pressure/Temperature Sensor (G395)
002 - Lower Limit Exceeded
Freeze Frame:
Fault Status: 01100010
Fault Priority: 2
Fault Frequency: 3
Reset counter: 92
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:41:21

Freeze Frame:
Temperature: 19.0°C
Temperature: 36.0°C
Load: 0.0 %
Absolute Pres.: 1.0 bar
RPM: 0 /min
Speed: 0.0 km/h
Current: 0.000 A
Temperature: 28.0°C

01592 - Air Quality Sensor (G238)
004 - No Signal/Communication
Freeze Frame:
Fault Status: 01100100
Fault Priority: 6
Fault Frequency: 1
Reset counter: 92
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:41:37

Freeze Frame:
Temperature: 19.0°C


-------------------------------------------------------------------------------
Address 09: Cent. Elect. (J519) Labels:. 8K0-907-063.clb
Part No SW: 8K0 907 063 HW: 8K0 907 063
Component: BCM1 1.0 H21 0253
Revision: 01021001 Serial number: 00000000111706
Coding: 690040B10014A7000001000000005F5F001D02080000014100 0000
Shop #: WSC 06325 000 00000
VCID: 6CDDF3398F10A62A11-8038

Subsystem 1 - Part No SW: 8K2 955 119 HW: 8T2 955 119 Labels: 1KX-955-119.CLB
Component: WWS 210308 H05 0060
Serial number: SWFBIE 0000468
Coding: 00FD11

Subsystem 2 - Part No SW: 8K0 955 559 HW: 8K0 955 559 Labels: 8K0-955-559.CLB
Component: RLS H04 0003
Serial number: 10081852
Coding: 025028

Subsystem 3 - Part No SW: 8K0 941 531 G HW: 8K0 941 531 G
Component: E1 - LDS H07 0070
Serial number: 00000000002103081233

2 Faults Found:
03020 - Local databus 2
012 - Electrical Fault in Circuit - Intermittent
Freeze Frame:
Fault Status: 00101100
Fault Priority: 2
Fault Frequency: 3
Reset counter: 132
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:41:00

01592 - Air Quality Sensor (G238)
004 - No Signal/Communication - Intermittent
Freeze Frame:
Fault Status: 00100100
Fault Priority: 3
Fault Frequency: 2
Reset counter: 132
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26


After another drive around and battery still able to start car:

Address 08: Auto HVAC (J255) Labels:. 8Tx-820-043-3Z.clb
Part No SW: 8T2 820 043 M HW: 8T2 820 043 M
Component: KLIMA 3 ZONEN H05 0120
Revision: D0000000 Serial number: 0112.03.080330
Coding: 64040000
Shop #: WSC 06325 000 00000
VCID: 3C7D0379BFF0F6AAC1-8068

4 Faults Found:
00457 - Control Module for Network (J519)
013 - Check DTC Memory
Freeze Frame:
Fault Status: 01101101
Fault Priority: 6
Fault Frequency: 9
Reset counter: 94
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:41:24

00256 - A/C Pressure/Temperature Sensor (G395)
008 - Implausible Signal
Freeze Frame:
Fault Status: 01101000
Fault Priority: 7
Fault Frequency: 10
Reset counter: 94
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:41:24

Freeze Frame:
Temperature: 19.0°C

00256 - A/C Pressure/Temperature Sensor (G395)
002 - Lower Limit Exceeded
Freeze Frame:
Fault Status: 01100010
Fault Priority: 2
Fault Frequency: 14
Reset counter: 94
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:41:21

Freeze Frame:
Temperature: 19.0°C
Temperature: 36.0°C
Load: 0.0 %
Absolute Pres.: 1.0 bar
RPM: 0 /min
Speed: 0.0 km/h
Current: 0.000 A
Temperature: 28.0°C

01592 - Air Quality Sensor (G238)
004 - No Signal/Communication
Freeze Frame:
Fault Status: 01100100
Fault Priority: 6
Fault Frequency: 13
Reset counter: 94
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:41:37

Freeze Frame:
Temperature: 19.0°C


-------------------------------------------------------------------------------
Address 09: Cent. Elect. (J519) Labels:. 8K0-907-063.clb
Part No SW: 8K0 907 063 HW: 8K0 907 063
Component: BCM1 1.0 H21 0253
Revision: 01021001 Serial number: 00000000111706
Coding: 690040B10014A7000001000000005F5F001D02080000014100 0000
Shop #: WSC 06325 000 00000
VCID: 6CDDF3398F10A62A11-8038

Subsystem 1 - Part No SW: 8K2 955 119 HW: 8T2 955 119 Labels: 1KX-955-119.CLB
Component: WWS 210308 H05 0060
Serial number: SWFBIE 0000468
Coding: 00FD11

Subsystem 2 - Part No SW: 8K0 955 559 HW: 8K0 955 559 Labels: 8K0-955-559.CLB
Component: RLS H04 0003
Serial number: 10081852
Coding: 025028

Subsystem 3 - Part No SW: 8K0 941 531 G HW: 8K0 941 531 G
Component: E1 - LDS H07 0070
Serial number: 00000000002103081233

3 Faults Found:
02095 - Component Protection Active
000 - - - Intermittent
Freeze Frame:
Fault Status: 00100000
Fault Priority: 1
Fault Frequency: 254
Reset counter: 134
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 19:49:00

03020 - Local databus 2
012 - Electrical Fault in Circuit - Intermittent
Freeze Frame:
Fault Status: 01101100
Fault Priority: 2
Fault Frequency: 226
Reset counter: 134
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:41:00

01592 - Air Quality Sensor (G238)
004 - No Signal/Communication - Intermittent
Freeze Frame:
Fault Status: 00100100
Fault Priority: 3
Fault Frequency: 13
Reset counter: 134
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:42:00

Address 47: Sound System (J525) Labels:. 8T0-035-223-ASC.clb
Part No SW: 8T0 035 223 J HW: 8T0 035 223
Component: DSP STD H07 0210
Revision: S1700000
Coding: 0203010101
Shop #: WSC 06325 000 00000
VCID: 356B165D9CDA27E23E-8060

1 Fault Found:
02095 - Component Protection Active
000 - - - Intermittent
Freeze Frame:
Fault Status: 00100000
Fault Priority: 4
Fault Frequency: 3
Reset counter: 134
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 19:35:24

Freeze Frame:
Voltage: 12.10 V
Temperature: 27.0°C
Bin. Bits: 00000001

Address 62: Door, Rear Left (J388) Labels:. 8K0-959-795.clb
Part No SW: 8K0 959 795 A HW: 8K0 959 795 A
Component: TSG HL H06 0170
Revision: Serial number: 0000006956709
Coding: 010002204001210001
Shop #: WSC 06325 000 00000
VCID: 40857789D318924A9D-8014

1 Fault Found:
02115 - Locking Unit for Central Locking
008 - Implausible Signal
Freeze Frame:
Fault Status: 01101000
Fault Priority: 3
Fault Frequency: 1
Reset counter: 92
Mileage: 147538 km
Time Indication: 0
Date: 2007.10.26
Time: 18:52:20

jagtoes

5 amps is not a suitable charger. Minimum should be 10 amps but better to have something around 25 amps to fully charge batteries. I have a 100 amp charger in my garage but also use a Ctek on my other stored cars.

SMac770

Well, starting point one would be resolve all the known DTCs, particularly since a number of them are electrical fault related.

Also, are you making use of the info as presented in this video? www.youtube.com/watch?v=lRcj1fQcWwU
You should be able to open all four doors, the trunk, and the hood. Then manually latch the locks for the doors and trunk. Then unplug the sensor for the hood. Then click the lock button on your remote and hear it chirp like it thinks everything is closed. The lights on the doors should go out. (that plug for the hood sensor; open the hood, stand in front of the car and look at the engine, place your hands forward on the lock carrier over the radiators, your right hand should land right about where the hood cable disconnect and the hood sensor plug are located, just on the under inside of the lock carrier cross bar)

The OP sounds like you were disconnecting the negative from the battery and placing an ammeter inbetween the battery and negative cable? While it doesn't help point to where the current is going, at least it tells you when the window of current draw exists so you know that it's of value to voltage drop test the fuses at that time.

Build date is a bit important; electrical wiring changes were done on a regular basis during B8.0.

Just hitting google comes back with a hit of a scan showing all kinds of similar HVAC codes as yours. Following that to the TSB, we come across these comments:

• The LIN cable connecting the vehicle electrical system control module, J519, to sensor G395 is pinched or cut. This affects the A4/S4, A5/S5 Coupe and Cabriolet, and Q5 vehicles. The A6 and A8 are not affected by this type of failure.
• The pressure sensor G395/G65 sends an incorrect signal that prevents bus silence and the battery is discharged. Tip: Sensor G395 is a LIN slave of the vehicle electrical system control module. The vehicle electrical system control module transfers the information provided by the sensor via the comfort data bus to the climate control module, J255.

So you might want to read through https://testing-public.carmd.com/Tsb...101765/A871449

Sam B

Hi SMac770 and jagtoes

Cheers for the reply, really appreciate it, so to answer some questions

Yes i got the info actually from that video and others online and did this test but didn't find anything. Did all the latch tricks etc but when the car was asleep started testing each fuse one at a time and any that had anything other than 0 i pulled out including AC related fuses. Made no difference.

That sensor being the possible culprit is very interesting as not long ago i had that sensor replaced due to it leaking after i went to get a recharge and found the leak. The whole AC is shot at the moment and i was planning on getting it repaired as the AC pump needs replacing anyway.

If i disconnect that sensor entirely is that sufficient? Tomorrow after work I'll look under the drivers side for any damaged cables and around the drivers headlight area.

From the scans can you see anything else i might want to check? The rear left door code could that be keeping the car awake? Also was is the definitive answer on how long it takes for the car to completely shut down? What's frustrating is the interval of how long the car takes to completely shut down, so for example i lock the car, i see the dashboard P parking light go out and the electronic handbrake light turn off and anything from 5 seconds to 10 minutes they will switch back on, then off again, then on again with that interval constantly changing.

Again Smac770 really appreciate the help/info

SMac770

"i see the dashboard P parking light go out and the electronic handbrake light turn off and anything from 5 seconds to 10 minutes they will switch back on, then off again, then on again with that interval constantly changing"
That's interesting. Clearly an indication that there's a serious problem with sleep. There's no reason any lights on the cluster/dash should be coming back on unless you've pressed the start/stop button. I would expect full outage to be when you open the door (ie, radio goes out, etc). If I have VCDS running and power off and then lock the doors (but not really since I have them all open but "manually" closed), I see current flow around 10amp then down to 7amp then 2amp then half amp then it cuts out after 30 seconds when OBD goes offline. So there shouldn't be any real current draw after 60 seconds at most I would expect.

03020 - Local databus 2 - Ross-Tech Wiki
Notice the reference to LIN bus. Same as what one of the G395's problems can impact.

I don't understand component protection on the J519, unless it's just relaying the one on the amp. Why do you have CP active on the amp?

https://forums.ross-tech.com/showthr...Door-rear-left
So maybe there's a wiring fault involving the relevant door harness and it's cascading your problems along the LIN bus?
Does the left rear door lock and unlock as expected? Open and not open as expected? You get the chirp when you lock the car with the key fob?
You may just be having a normal lock actuator failure problem.

So going back to the LIN bus idea. G238 air quality sensor and G395 A/C pressure/temp sensor are both connected to B549 LIN bus connection 2, which connects to J519 connector T16b pin 4.
Another thing on that is the "driving profile selection switch module E592". This is the row of driving controls between the CD changer and the climate controls on MMI cars (disable start/stop, disable ESP, etc).
Also the J530 garage door opener.
Also the J799 and J800 seat ventilation control module, if you have vented seats.

So going back to that TSB, I'd be going over all the wiring and devices attached to J519 T16b pin 4.
I didn't finish processing this video, but it talked about looking at a LIN bus diagnostic, so you might find it educational for this issue.
www.youtube.com/watch?v=bLmUmBnLpTc

Sam B

Update for you, I took out the headlight and the trim underneath the steering wheel, so far i cannot find anything. I've disconnected the pressure sensor so far no luck, I'm convinced its wire related as sometimes the wake up signal doesnt happen, then after driving it might start again and the interval keeps changing.

The TSB link you sent me said behind the drivers headlight, then i realised that would be the other side for me

So going to drop the trim in the passenger footwell later today

Adam May

did you have any luck sorting this? I’m having intermittent battery drain issues some days it’s fine some days it goes dead overnight and all the dash lights are on

LucasSmalley23

Dont know if this helps had a bad battery drain on my audi a4 2009 and it was to do with the navigation system in the boot the big amp on top and failed even though the nav still worked fine replaced that and was fine after that