All sorts of random going on........

[Joe.Woollam]

Hi All new here firstly would like to thank all members as I have already managed to find a number of solutions just reading this forum.

I have recently purchased an Audi A4 B6, woke up the day after purchasing to find that the battery had drained over night, after a little digging and a lot of reading we figured this was due to a faulty battery on the siren module in the right hand side of the boot, sort a guide for a DIY fix rather than a new unit (cut into the unit carefully with a junior hacksaw around the weld seem remove old exploded battery and use an external box to house 6 AA rechargeable batteries and solder the terminals appropriately)

How ever I'm now getting all sorts of random, the central locking is trying to lock the car every couple of minutes when the car is locked, eventually the alarm, both siren and hazards will go off, removing the central locking fuse and locking it with the key stops the car trying to constantly lock itself eventually the hazards will start to go off, if i let the car auto lock after a few minutes rather than using the key (central locking fuse still removed) the alarm does not seem to go off and the car does not appear to try to lock itself constantly.

I am aware of the inherent CCU problem but any advise, help, ideas would be greatly appreciated,


Thank you for taking the time to read my post :)

Joe.Woollam

[Rob69]

what happens if you disconnect the home made battery pack and leave it like that?

[Joe.Woollam]

I'm guessing the battery would drain itself as it was before (the car battery not the alarm battery) am unable to try this during the week as i need the car for work, the battery fix was from a guide we fount online and has worked for many people could this cause some time of resistance issue with the alarm system?

[Rob69]

But was the main car battery not draining due to it being connected to the fried alarm siren battery? I had random alarm problems on a touran several years ago and ended up just removing the siren, no one takes any notice of them anyway. just thinking your home made battery pack will have different current consumption and the siren circuit board may also be damaged and maybe be upsetting the CC module.

[Joe.Woollam]

sorry I was at work just tried disconnecting siren and hazards are constantly on :/

[Joe.Woollam]

Also does anyone know if i will cause any issue if i remove the onboard power supply unit (j519) as i know if you replace it you need to re code it with vag com just wondering if it forgets any information if i disconnect it?

[Joe.Woollam]

if anyone reading this post is having these issues popping fuse 34 I think it is (top left of bottom square 15A fuse) and letting the car auto lock rather than using the key (you will have to put the fuse back in before starting the car else alarms etc will be going off) will get you buy for now until I find a fix.