Battery drain still happening... Completely stumped :( **UPDATE**

[Craigh1983]

It's not that it doesn't let the Can bus sleep it just attempts to draw current to charge itself. The siren is a control unit in its own right and communicates via Lin bus single wire. If the master unit cannot see it then it continually sends a signal looking for it and also let's it draw current from the battery to charge itself, until the voltage stored reaches a set level. With a faulty cell this cannot be achieved, hence the drain - continuous draw.

Ok so this is all kinda starting to make sense to me now...

I'm going to sound a bit stupid again though and im just trying to make sense of it all... how come my stereo fuse is active and using a huge amount of power? is it because of the master control unit is constantly sending that signal?

[MJ]

That may be a separate issue entirely or it might be connected because one system is over ruling the other. The anti theft system has a high priority when it comes to power usage.

[Craigh1983]

Having the new alarm fitted on Wednesday :)

Will be great if this sorts the issue. Everything is pointing to the siren but I'm tying not to get my hopes up.

Just did another check on the fuses and it's still draining. Same values as before so I hope they are still there when I take it to Ed on Wednesday!!

[SI-R32]

Did you see if you have an amplifier under the seat for fuse 18?

[Craigh1983]

Did you see if you have an amplifier under the seat for fuse 18?

Yep. There was an amp there. Never noticed it before!

[Craigh1983]

Thanks for letting me know what that fuse was for Si

[Eddie-NL]

Hopefully sorted Now

New Alarm Horn fitted - still battery drain - at least the car is protected now
New CECM fitted - No battery drain when checked

New Gateway fitted as there was a reoccurring fault, Comfort CAN in single wire mode. Gateway at fault

[SI-R32]

really glad this sounds like its finally over, hopefully Ed has sorted things a final time for you and you can finally enjoy your golf. fingers crossed mate

[Craigh1983]

really glad this sounds like its finally over, hopefully Ed has sorted things a final time for you and you can finally enjoy your golf. fingers crossed mate

Honestly mate me too! This car has stressed me out way too much! The problem
Has been going on for over a month now with all the electronics failing first of all.

Ed was an absolute star today. Spent all day on my car and had the dash out soldering wires n all sorts. Sorted it in the end so massive thanks to you mate for that!!

Also John (Doylebros) on the forum has been a massive help. Helping me out over the phone and sending me all the parts... Twice! Also everyone else on the forum thank you for your help! John_A and Matto for doing scans for me! What a great bunch of people!

Ed kindly pointed out that I have the start of some rust on the wheel arches lol I look forward to now trying to get that sorted hahaha

[brummo]

Hopefully sorted Now

New Alarm Horn fitted - still battery drain - at least the car is protected now
New CECM fitted - No battery drain when checked

New Gateway fitted as there was a reoccurring fault, Comfort CAN in single wire mode. Gateway at fault

Hi all, i appreciate that this topic is old but i'm trying to diagnose battery drain.  I've done loads of reading up and just wondered if there is a consensus on what is the key issue, i.e. is it the alarm horn siren (which doesn't work on mine, or the door lock mechanism, again not working on mine on the passenger side.  Tried a replacement CCM no joy, next step is possibly the CECM.  Does coding the alarm out help?

Currently drawing 98ma

Here are the relevant parts of my scan

Address 46: Central Conv. Labels:. 1K0-959-433-MIN.clb
Part No: 1K0 959 433 T
Component: 0W KSG 0560
Coding: 81E802087F2D8505485BC61000
Shop #: WSC 00000 785 00200
VCID: 4189F0031889C38E4D-8014
Subsystem 1 - Component: Sounder No Answer
Subsystem 2 - Component: NGS No Answer
Subsystem 3 - Component: IRUE No Answer
3 Faults Found:
01135 - Interior Monitoring Sensors
004 - No Signal/Communication
00323 - Vehicle Inclination Sensor (G384)
004 - No Signal/Communication
01134 - Alarm Horn (H12)
004 - No Signal/Communication
-------------------------------------------------------------------------------
Address 52: Door Elect, Pass. Labels: 1K0-959-702-MIN1.lbl
Part No: 1K0 959 702 E
Component: Tuersteuergeraet 09 0116
Coding: 0000052
Shop #: WSC 01279 785 00200
VCID: 3169A0C3A829530EBD-8064
2 Faults Found:
01553 - Motor for Central Locking; Passenger Door (V57); Lock
012 - Electrical Fault in Circuit
00929 - Locking Module for Central Locking; Front Passenger Side (F221)
008 - Implausible Signal

[Grevling89]

Hi all, i appreciate that this topic is old but i'm trying to diagnose battery drain.  I've done loads of reading up and just wondered if there is a consensus on what is the key issue, i.e. is it the alarm horn siren (which doesn't work on mine, or the door lock mechanism, again not working on mine on the passenger side.  Tried a replacement CCM no joy, next step is possibly the CECM.  Does coding the alarm out help?

Currently drawing 98ma

Here are the relevant parts of my scan

Address 46: Central Conv. Labels:. 1K0-959-433-MIN.clb
Part No: 1K0 959 433 T
Component: 0W KSG 0560
Coding: 81E802087F2D8505485BC61000
Shop #: WSC 00000 785 00200
VCID: 4189F0031889C38E4D-8014
Subsystem 1 - Component: Sounder No Answer
Subsystem 2 - Component: NGS No Answer
Subsystem 3 - Component: IRUE No Answer
3 Faults Found:
01135 - Interior Monitoring Sensors
004 - No Signal/Communication
00323 - Vehicle Inclination Sensor (G384)
004 - No Signal/Communication
01134 - Alarm Horn (H12)
004 - No Signal/Communication
-------------------------------------------------------------------------------
Address 52: Door Elect, Pass. Labels: 1K0-959-702-MIN1.lbl
Part No: 1K0 959 702 E
Component: Tuersteuergeraet 09 0116
Coding: 0000052
Shop #: WSC 01279 785 00200
VCID: 3169A0C3A829530EBD-8064
2 Faults Found:
01553 - Motor for Central Locking; Passenger Door (V57); Lock
012 - Electrical Fault in Circuit
00929 - Locking Module for Central Locking; Front Passenger Side (F221)
008 - Implausible Signal

Did you try the reverse engineering method of singling out what circuit that's causing the drain?

This video helped me loads when troubleshooting a parasitic battery drain:

. Gentle warning about an immensely American aesthetic and way of speaking, but the info is good.