Advice please, my alarm is being triggered and flattens the battery

PlasticMac

Member
I think you should test the alarm, sit in the car, lock with the remote, after a minute or two, (not sure how long, after setting untill alarm is actually armed), wave your arms about. If it triggers, hazards and horn, maybe you can rule out the alarm as a cause of battery drain, unless you think no one would have noticed if it triggered at night.
Mac.
 

Crikeymikey

A2OC Donor
HI All
I had a similar random alarm fault on my in laws 2003 polo 1.4 tdi. On a full check via vag com on the vehicle, i couldn't find anything wrong with it. All Doors showed locked unlocked or safe, boot lock same. My retired mother in law only uses her polo for shopping and family visits(no more than 50 miles per week) so i thought maybe low battery. So I took battery off and charged it up, took car out for an hour. After a week of no false alarms the car decided to alarm at 2 am in the morning. Very stress full for her. So again i scanned her car, again no issue found. So i manually disconnected the interior motion sensor, as for some strange reason the car wouldn't allow me to disable interior monitoring. Either via vagcom or via interior push button. It has been over 6 months now and no alarm. Could be worth a try??
Best of luck
The alarm isn't going off, Steve. Only the hazards apparently.
 

stevec

Member
Hi All
The relay for the hazards also powers the indicators so you have two separate circuits. I have had a hazard/indicator relay fail on one of my A2's and it gave me no indicators, but the hazards would work. I have also had an indicator arm fail and this would give a random click from the relay whilst driving the car, but no flash from the indicators.
With the age of our A2's now i wouldn't rule out anything. This fault could be the hazard relay side has failed or it being triggered by a faulty hazard switch or via the alarm. Either way and as you going to be fault finding, I would also fully test the alarm circuit to make sure it is working with the sounder.
As a precaution, I would also scan and record the measuring blocks for the last 4 alarm trigger points.
Best of luck
Steve
 

2work

Admin Team
Hi All
The relay for the hazards also powers the indicators so you have two separate circuits. I have had a hazard/indicator relay fail on one of my A2's and it gave me no indicators, but the hazards would work. I have also had an indicator arm fail and this would give a random click from the relay whilst driving the car, but no flash from the indicators.
With the age of our A2's now i wouldn't rule out anything. This fault could be the hazard relay side has failed or it being triggered by a faulty hazard switch or via the alarm. Either way and as you going to be fault finding, I would also fully test the alarm circuit to make sure it is working with the sounder.
As a precaution, I would also scan and record the measuring blocks for the last 4 alarm trigger points.
Best of luck
Steve
Morning Steve,

Fingers crossed the fault has since been cured with a replacement hazard relay which Steph had fitted on Saturday. Of note the end cap on the existing hazard relay was missing, would this allow easier access for moisture damage maybe. The alarm module wasn’t swapped over as it appeared to be ok, but difficult to determine as it’s not a consistent fault.

Hopefully Steph will report back in a few days with some results. I still have an alarm module ready to dispatch should it be necessary.

Like you say though, with the age of our aluminium friends with the possibility of moisture ingress during its life, nothing can be ruled out.

Kind regards,

Tom
 

steve_c

Grumpy OAP & A2OC Donor
Good evening. Belatedly, an update to the thread.

Tom - @2work - very generously invited me over to Coalville, where he offered to swap both my hazard relay and my alarm siren over with known working parts, and I drove over on Saturday morning. Thanks to his expertise, my hazard relay has now been replaced, but after further discussion with Tom, the alarm siren has been left in situ. I made this (possibly mistaken) decision because the existing siren clearly still works, because it never shows up as a fault on VCDS unless my battery has run flat, and to a lesser extent because I sensed that other participants in this discussion were moving to the same view.

Tom ran his own VCDS checks on my car, both with the engine off and with it running, and nothing relevant showed up at all.

We spent the rest of the morning doing a few lesser jobs on my car, and then I had a look round Tom's impressive fleet, before heading back to Norwich.

So a massive thank you to Tom for everything, his time, his company, his hospitality, his knowledge and his practical skills.

Because the battery in my A2 has been flattening at irregular intervals, it will be quite some time before I know whether or not we have solved the issue. One other possibility is parasitic drain on the battery which is not that easy to test for when the car is parked on a public road. However, when I have checked my battery with my multimeter, it always shows as fully charged.

Thanks once again to Tom, and to everyone else who responded, both here and in private messages. All your advice was helpful and appreciated.
 

2work

Admin Team
Good evening. Belatedly, an update to the thread.

Tom - @2work - very generously invited me over to Coalville, where he offered to swap both my hazard relay and my alarm siren over with known working parts, and I drove over on Saturday morning. Thanks to his expertise, my hazard relay has now been replaced, but after further discussion with Tom, the alarm siren has been left in situ. I made this (possibly mistaken) decision because the existing siren clearly still works, because it never shows up as a fault on VCDS unless my battery has run flat, and to a lesser extent because I sensed that other participants in this discussion were moving to the same view.

Tom ran his own VCDS checks on my car, both with the engine off and with it running, and nothing relevant showed up at all.

We spent the rest of the morning doing a few lesser jobs on my car, and then I had a look round Tom's impressive fleet, before heading back to Norwich.

So a massive thank you to Tom for everything, his time, his company, his hospitality, his knowledge and his practical skills.

Because the battery in my A2 has been flattening at irregular intervals, it will be quite some time before I know whether or not we have solved the issue. One other possibility is parasitic drain on the battery which is not that easy to test for when the car is parked on a public road. However, when I have checked my battery with my multimeter, it always shows as fully charged.

Thanks once again to Tom, and to everyone else who responded, both here and in private messages. All your advice was helpful and appreciated.
Evening Steph,

It was a pleasure to host you, finally met you being able to put a face to the username and to tinker with your A2 in an attempt to get to the bottom of your woes. Just happy to assist a fellow member with my limited knowledge. With the hive brain at work and my FOC time/tools I'm hoping it's resolved for you, of course time will tell.

Remember that I have the alarm module ready to dispatch should it be necessary so do keep us all updated, if it turned out to be required then I'd even fit it FOC but that would mean another trip over to 2work Towers.

Glad you like the fleet and their considered upgrades/retrofits, a labour of love but not finished yet!

Kind regards,

Tom
 

steve_c

Grumpy OAP & A2OC Donor
Well, it's taken a long time, but I suspect that I now know what it is that is flattening my battery from time to time.

The microswitch in my driver's door lock is failing, and the central locking is being triggered as a consequence. The click from the central locking is possibly what sets off the alarm, although it may be that the VCDS faults showing for that are simply a consequence of the battery being drained.

At least I now know my next steps. Either buy a new lock and get it fitted, or get the solder on the PCB reflowed for the existing lock.
 

2work

Admin Team
Morning Steph,

I'm inclined to believe that the microswitches aren't linked to your power drain woes and are only appearing now as a result of the battery draining again. Whilst here last weekend the microswitches didn't present themselves as an issue on the very first and final scan. I also don't recall your locks cycling when the ignition was switched on. I also remember that after swapping the B pillar button over that both the alarm interior monitor and fuel flap buttons work just fine. I wonder if we should have just swapped the alarm modules over as a precaution.

Here's the initial VCDS report:
Code:
Saturday,17,September,2022,11:13:02:07337
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64
VCDS Version: 22.9.0.0 (x64)  HEX-NET CB: 0.4623.4
Data version: 20220830 DS341.0
www.Ross-Tech.com


VIN: WAUZZZ8Z82N005731   License Plate:


Chassis Type: 8Z (8Z - Audi A2 (2000 > 2005))
Scan: 01 02 03 08 15 16 17 18 37 45 46 56 57 75 76 77
 
VIN: WAUZZZ8Z82N005731
-------------------------------------------------------------------------------
Address 01: Engine        Labels: 036-906-034-APE.lbl
   Part No: 036 906 034 EG
   Component:  MARELLI 4MV G     4030
   Coding: 00051
   Shop #: WSC 02138
   VCID: 5BF64C56CB39295576-4B5C
   WAUZZZ8Z82N005731     AUZ7Z0A1863783

1 Fault Found:
18043 - Powertrain Data Bus
            P1635 - 35-10 - Missing Message from A/C Controller - Intermittent
Readiness: 0000 0100

-------------------------------------------------------------------------------
Address 03: ABS Brakes        Labels: 8Z0-907-379-MK20.lbl
   Part No: 8Z0 907 379 B
   Component: ESP     20    CAN  V015
   Coding: 10758
   Shop #: WSC 00000
   VCID: 47DE802667B15DB5C2-4B3C

No fault code found.

-------------------------------------------------------------------------------
Address 08: Auto HVAC        Labels: None
   Part No: 8Z0 820 043 G
   Component: A2-KLIMAVOLLAUTOMAT 0510
   VCID: 3A38E9D22443305D4D-258E

1 Fault Found:
00818 - Sensor for Evaporator Outlet Temperature (G263)
            30-00 - Open or Short to Plus

-------------------------------------------------------------------------------
Address 15: Airbags        Labels: 8Z0-959-655.lbl
   Part No: 8Z0 959 655 E
   Component: Airbag Front+Seite 5005
   Coding: 00102
   Shop #: WSC 02152
   VCID: 4ED0B50288CB8CFD81-5160

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments        Labels: 8Z0-920-xxx-17.lbl
   Part No: 8Z0 920 980 K
   Component: KOMBI+WEGFAHRS. VDO D05
   Coding: 05442
   Shop #: WSC 18184
   VCID: 49DA861E71A5ABC5D4-5160
   WAUZZZ8Z82N005731     AUZ7Z0A1863783

2 Faults Found:
01304 - Radio
            49-10 - No Communications - Intermittent
01320 - Control Module for Climatronic (J255)
            49-10 - No Communications - Intermittent

-------------------------------------------------------------------------------
Address 37: Navigation        Labels: 8E0-035-192-RNSE.clb
   Part No SW: 8P0 035 193 G    HW: 8P0 035 193 G
   Component: RNS-E PU EU     H06 0290
   Revision: 0000012S    Serial number: AUZBZ7MD200061
   Coding: 0500111
   Shop #: WSC 18184 210 93639
   VCID: 3424C7EA5627C62D97-50F4

2 Faults Found:
00625 - Vehicle Speed Signal
            004 - No Signal/Communication
             Freeze Frame:
                    Fault Status: 01100100
                    Fault Priority: 5
                    Fault Frequency: 1
                    Reset counter: 165
                    Time Indication: 0
                    Date: 2022.09.16
                    Time: 16:31:01

             Freeze Frame:
                    Mileage: 655350 km
                    Count: 1609
                    Clock: 16:30

02454 - Microphone Unit (in Front Roof Module) (R164)
            011 - Open Circuit - Intermittent
             Freeze Frame:
                    Fault Status: 00101011
                    Fault Priority: 5
                    Fault Frequency: 1
                    Reset counter: 214
                    Time Indication: 0
                    Date: 2022.09.17
                    Time: 09:48:54


-------------------------------------------------------------------------------
Address 45: Inter. Monitor        Labels: 8E0-951-177.lbl
   Part No: 8Z0 951 177
   Component: Innenraumueberw.    D04
   Coding: 00001
   Shop #: WSC 00000
   VCID: 55E25A6EAD1DFF2540-513C

No fault code found.

-------------------------------------------------------------------------------
Address 46: Central Conv.        Labels:. 8Z0-959-433.lbl
   Part No: 8Z0 959 433 AF
   Component: Komfortgerát TBD    1210
   Coding: 07883
   Shop #: WSC 18184
   VCID: 0A5879123423E0DD1D-4B00

   Subsystem 1 - Part No: 8Z2959802
   Component: Tõrsteuer.FS BRM 0001

   Subsystem 2 - Part No: 8Z2959801
   Component: Tõrsteuer.BF BRM 0001

1 Fault Found:
01320 - Control Module for Climatronic (J255)
            49-10 - No Communications - Intermittent

-------------------------------------------------------------------------------
Address 56: Radio        Labels: 8E0-035-192-RNSE.clb
   Part No SW: 8P0 035 193 G    HW: 8P0 035 193 G
   Component: RNS-E PU EU     H06 0290
   Revision: 0000012S    Serial number: AUZBZ7MD200061
   Coding: 0500111
   Shop #: WSC 18184 210 93639
   VCID: 3424C7EA5627C62D97-50F4

2 Faults Found:
00625 - Vehicle Speed Signal
            004 - No Signal/Communication
             Freeze Frame:
                    Fault Status: 01100100
                    Fault Priority: 5
                    Fault Frequency: 1
                    Reset counter: 165
                    Time Indication: 0
                    Date: 2022.09.16
                    Time: 16:31:01

             Freeze Frame:
                    Mileage: 655350 km
                    Count: 1609
                    Clock: 16:30

02454 - Microphone Unit (in Front Roof Module) (R164)
            011 - Open Circuit - Intermittent
             Freeze Frame:
                    Fault Status: 00101011
                    Fault Priority: 5
                    Fault Frequency: 1
                    Reset counter: 214
                    Time Indication: 0
                    Date: 2022.09.17
                    Time: 09:48:54


End----------(Elapsed Time: 03:25, VBatt start/end: 11.9V/12.0V)-----------


Here's the final VCDS report:
Code:
Saturday,17,September,2022,11:25:05:07337
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64
VCDS Version: 22.9.0.0 (x64)  HEX-NET CB: 0.4623.4
Data version: 20220830 DS341.0
www.Ross-Tech.com


VIN: WAUZZZ8Z82N005731   License Plate:


Chassis Type: 8Z (8Z - Audi A2 (2000 > 2005))
Scan: 01 02 03 08 15 16 17 18 37 45 46 56 57 75 76 77
 
VIN: WAUZZZ8Z82N005731
-------------------------------------------------------------------------------
Address 01: Engine        Labels: 036-906-034-APE.lbl
   Part No: 036 906 034 EG
   Component:  MARELLI 4MV G     4030
   Coding: 00051
   Shop #: WSC 02138
   VCID: 5BF64C56CB39295576-4B5C
   VINID: 9D196AAAA22A2027800051C3047C0BDD97
   WAUZZZ8Z82N005731     AUZ7Z0A1863783

No fault code found.
Readiness: 1110 0101

-------------------------------------------------------------------------------
Address 03: ABS Brakes        Labels: 8Z0-907-379-MK20.lbl
   Part No: 8Z0 907 379 B
   Component: ESP     20    CAN  V015
   Coding: 10758
   Shop #: WSC 00000
   VCID: 47DE802667B15DB5C2-4B3C

No fault code found.

-------------------------------------------------------------------------------
Address 08: Auto HVAC        Labels: None
   Part No: 8Z0 820 043 G
   Component: A2-KLIMAVOLLAUTOMAT 0510
   VCID: 3A38E9D22443305D4D-2596

1 Fault Found:
00818 - Sensor for Evaporator Outlet Temperature (G263)
            30-00 - Open or Short to Plus

-------------------------------------------------------------------------------
Address 15: Airbags        Labels: 8Z0-959-655.lbl
   Part No: 8Z0 959 655 E
   Component: Airbag Front+Seite 5005
   Coding: 00102
   Shop #: WSC 02152
   VCID: 4ED0B50288CB8CFD81-5160

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments        Labels: 8Z0-920-xxx-17.lbl
   Part No: 8Z0 920 980 K
   Component: KOMBI+WEGFAHRS. VDO D05
   Coding: 05442
   Shop #: WSC 18184
   VCID: 49DA861E71A5ABC5D4-5160
   WAUZZZ8Z82N005731     AUZ7Z0A1863783

No fault code found.

-------------------------------------------------------------------------------
Address 37: Navigation        Labels: 8E0-035-192-RNSE.clb
   Part No SW: 8P0 035 193 G    HW: 8P0 035 193 G
   Component: RNS-E PU EU     H06 0290
   Revision: 0000012S    Serial number: AUZBZ7MD200061
   Coding: 0500111
   Shop #: WSC 18184 210 93639
   VCID: 3424C7EA5627C62D97-50F4

No fault code found.

-------------------------------------------------------------------------------
Address 45: Inter. Monitor        Labels: 8E0-951-177.lbl
   Part No: 8Z0 951 177
   Component: Innenraumueberw.    D04
   Coding: 00001
   Shop #: WSC 00000
   VCID: 55E25A6EAD1DFF2540-513C

No fault code found.

-------------------------------------------------------------------------------
Address 46: Central Conv.        Labels:. 8Z0-959-433.lbl
   Part No: 8Z0 959 433 AF
   Component: Komfortgerát TBD    1210
   Coding: 07883
   Shop #: WSC 18184
   VCID: 0A5879123423E0DD1D-4B00

   Subsystem 1 - Part No: 8Z2959802
   Component: Tõrsteuer.FS BRM 0001

   Subsystem 2 - Part No: 8Z2959801
   Component: Tõrsteuer.BF BRM 0001

No fault code found.

-------------------------------------------------------------------------------
Address 56: Radio        Labels: 8E0-035-192-RNSE.clb
   Part No SW: 8P0 035 193 G    HW: 8P0 035 193 G
   Component: RNS-E PU EU     H06 0290
   Revision: 0000012S    Serial number: AUZBZ7MD200061
   Coding: 0500111
   Shop #: WSC 18184 210 93639
   VCID: 3424C7EA5627C62D97-50F4

No fault code found.

End----------(Elapsed Time: 03:34, VBatt start/end: 13.6V/13.4V)-----------

The alarm module is still in the dining room and can send it to you if need be or even fit it for you if you're going to be local anytime soon. I also have a drives door lock module if it does turn out to be the culprit but not convinced it is. Always happy to help out a fellow member.

Kind regards,

Tom
 

steve_c

Grumpy OAP & A2OC Donor
I'm inclined to believe that the microswitches aren't linked to your power drain woes and are only appearing now as a result of the battery draining again. Whilst here last weekend the microswitches didn't present themselves as an issue on the very first and final scan. I also don't recall your locks cycling when the ignition was switched on. I wonder if we should have just swapped the alarm modules over as a precaution.

Good morning Tom,

It clearly doesn't happen every time, but my locks do now cycle quite often when I start the engine. I've been aware of this since I fitted the later AF CCCU, which gives the central locking a far louder click. Six months ago it was a rare event, but now it's reached the point where it happens as often as not.
 

2work

Admin Team
Hello Steph,

It would be annoying if the CCCU has failed. Can you confirm there is not moisture in the passengers footwell compartment as these particular revisions are quite robust but of course can fail.

Of note, I do have a spare known good AF CCCU here you can try as this is a simple to swap over, it’s destined to go I to the Pine Green AUA as it has the earlier style CCCU but is working fine right now so no rush to swap it over.

You’ll have to pair your existing remote fobs to it but recall you saying that wouldn’t be an issue and well within your ability. I’d be happy to send this to you for testing purposes and leave it fitted for a couple of weeks.

Let me know your thoughts on the alarm module, drivers door lock module and AF CCCU offer to create a Triggers Broom convenience circuit.

Kind regards,

Tom
 

steve_c

Grumpy OAP & A2OC Donor
It would be annoying if the CCCU has failed. Can you confirm there is not moisture in the passengers footwell compartment as these particular revisions are quite robust but of course can fail.

Of note, I do have a spare known good AF CCCU here you can try as this is a simple to swap over, it’s destined to go I to the Pine Green AUA as it has the earlier style CCCU but is working fine right now so no rush to swap it over.

You’ll have to pair your existing remote fobs to it but recall you saying that wouldn’t be an issue and well within your ability. I’d be happy to send this to you for testing purposes and leave it fitted for a couple of weeks.

Tom, as always, thanks for the kind offer.

Firstly, I must say that my battery hasn't gone flat since my visit to you. Right now, it is holding an excellent charge.

No, there's no moisture in the passenger footwell, at least there wasn't when I swapped the CCCU over, and I've not driven the car in anything worse than light showers since.

The problem I have is difficult to get to the bottom of because it is so intermittent. It was five months between my battery first going flat and the second time, and I had long since thought that my CCCU change had resolved the issue.

I really feel at this point that I need to get the car to @timmus at some point for a thorough check over. If I need another CCCU I'm sure he will provide one. With the nights starting to draw in, it may well be that I get through the winter by swapping the battery over when it becomes necessary.

Thanks once again for the offer. I shall keep it in mind, but won't take you up on it right now.
 

Stan H

Member
Tom, as always, thanks for the kind offer.

Firstly, I must say that my battery hasn't gone flat since my visit to you. Right now, it is holding an excellent charge.

No, there's no moisture in the passenger footwell, at least there wasn't when I swapped the CCCU over, and I've not driven the car in anything worse than light showers since.

The problem I have is difficult to get to the bottom of because it is so intermittent. It was five months between my battery first going flat and the second time, and I had long since thought that my CCCU change had resolved the issue.

I really feel at this point that I need to get the car to @timmus at some point for a thorough check over. If I need another CCCU I'm sure he will provide one. With the nights starting to draw in, it may well be that I get through the winter by swapping the battery over when it becomes necessary.

Thanks once again for the offer. I shall keep it in mind, but won't take you up on it right now.
Slightly different angle, l'm no auto electrician or have VCAS but had an odd alarm going off issue on my 52 plate A4 which turned out to be one of the connections in the plug to the alarm which had corroded. A bit of a job to get it out from where they had hidden it for anti theft measures.
 

Crikeymikey

A2OC Donor
Sorry to hear it wasn't the hazard relay, Steve. I would have bet the farm on that. Fingers crossed that you get to the bottom of it ASAP.
 

steve_c

Grumpy OAP & A2OC Donor
Sorry to hear it wasn't the hazard relay, Steve. I would have bet the farm on that. Fingers crossed that you get to the bottom of it ASAP.

It's still possible that the locks cycling and the battery going flat are two separate issue (although it seems unlikely). So I may yet find that I benefit from the change of hazard relay.

This started early in February, so I'm now working back through the history so that I can have an accurate timeline in front of me.
 

2work

Admin Team
It's still possible that the locks cycling and the battery going flat are two separate issue (although it seems unlikely). So I may yet find that I benefit from the change of hazard relay.

This started early in February, so I'm now working back through the history so that I can have an accurate timeline in front of me.
Evening Steph,

I never realised this was something that has been going on for so long, certainly not going back to the cooler months of February.

As this is the case then I agree that dry solder joints could well be a problems here, maybe not the cause of the battery drain issue though.

Project OEM has dry solder joints on the rear door modules which only make the central locking cycle during the colder months of the year. They have just this week started to fail again and cause the cycling of the locks when the ignition is switched on. In the warmer months I have no issue what so ever. I guess this must be the slightest of expansion and contraction of the PCB as the ambient temperature changes. Do you experience that same symptoms as the weather changes?

I’ll get to reflowing the joints one day but it’s never bothered me that much and been extant since purchasing the vehicle March 2020. I’ve certainly not experienced any kind of power drain though which makes me think your main issue has got to be something else.

I’m sure other Tom will get to the bottom of it soon enough though but my money is on the alarm module or the CCCU, if not then a loom issue somewhere. That said if you’ve not had a flat battery since the swapping of the hazard relay then it might well be the end of your power woes.

Kind regards,

Tom
 

steve_c

Grumpy OAP & A2OC Donor
I agree that dry solder joints could well be a problems here, maybe not the cause of the battery drain issue though.

At last, I have absolute certainty on the locks cycling issue. It was caused, not by dry solder joints in any of the locks, but by a defective remote fob that came with my AF CCCU. Swapping over to my other key fixed the issue, and now I've got the troublesome fob apart I can see where the problem is.

So a quick dab of solder and that'll be fixed. And it may yet be that the replacement relay hazard has sorted out the battery drain issue, although only time will tell.
 

2work

Admin Team
At last, I have absolute certainty on the locks cycling issue. It was caused, not by dry solder joints in any of the locks, but by a defective remote fob that came with my AF CCCU. Swapping over to my other key fixed the issue, and now I've got the troublesome fob apart I can see where the problem is.

So a quick dab of solder and that'll be fixed. And it may yet be that the replacement relay hazard has sorted out the battery drain issue, although only time will tell.
Morning Steph,

Good luck with this fault. I hope this is the end of your battery flattening issues Sir.

Kind regards,

Tom
 
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