Battery drain, it's my fault

[ballbagbagins]

Hi, bought a new to me 2006 golf r32 recently. It had a reverse camera poking out one of the rear number plate lights.

As it doesn't work with the after market head unit I cut the camera off the cable and pushed the cable back into the bumper.

Now my battery keeps dying, I assume my bodgery has caused this.

How can I prove the camera removal is draining the battery and how can I fix it?

Please go very slowly with any help, electrics are one of the many things I can't understand.

Thanks

[hkr91]

Easiest thing to do is pull the head unit out and have a look at the reverse camera connection - unplug it to isolate the camera and see if you're still getting the drain.

Otherwise (and if it doesnt work), I'd look at using a multimeter (on the current/amps setting), then pull each fuse (one by one) and see what affects the values.

Check on YouTube how to do it bud, you'll have to disconnect the negative terminal from the battery, then put one of the leads on the battery negative post and the other on the negative lead.

[hkr91]

As a side thought - if its not connected to the head unit, you can trace the the rest of the wiring you've cut and isolate it (open the wires and make sure they're not touching eachother/touching the body)

Edit: wondering if it's connected to the hand brake switch as an earth/feed too.

[squonk]

Reversing cameras usually get their power from the reversing lights so that they are only active when you are in reverse gear. Handbrake switches are usually connected to a head unit that has the capability of playing back video files so that it disables the feature unless the car is stopped and the handbrake is on.

I doubt that your fault is related to the removal of the camera. If there was a short then either a fuse would blow or a wire would melt. As hkr91 says, connect a multimeter in series with the battery and set it to the 10A scale, see what the draw is and then remove each fuse one by one until the draw goes away. You will then know which circuit is causing the draw and you can investigate further.

Have any other accessories been fitted such as a large amplifier? I had this problem on a Jeep once. The amplifier wasn't turning off and it was flattening the battery over night.

The other possible culprit may be the alternator. If the diodes are breaking down they could be shorting gradually to earth. The charge light doesn't always come on when this happens and the alternator will still work until the fault gets worse. Try disconnecting it and see what the current draw is then.

[ChasR]

Given this car would be new enough to have CANBUS, it may have had the headunit wired without a CANBUS box, mainly as the CANBUS conversion boxes are dear.

I'd look into getting this done.

I'll say more later but I need to get to work

[ballbagbagins]

Thanks everyone, i have a few things to investigate now. I have a unused multimeter so will get on YouTube at the weekend.

Chas, I've actually bought a newer gateway control module, is that the same thing what you mention?

I bought it as I have polarfis to install and after checking in vcds, read that i needed a more recent gateway thingy.

[ballbagbagins]

I'm pretending I've made progress.

The car is a Japanese import so had a vics system installed, it's a live traffic update thing.

Whilst rummaging behind the glovebox and head unit I removed it.

[ballbagbagins]

Traced the cable from the rear reg lights to the front of the car where the single cable splits into two.

[ballbagbagins]

One of those cables runs to behind the head unit to this, which i guess was connected to the previous VW OE head unit.

[ballbagbagins]

This is the second of those two cables. My tiny mind thinks this is power?

[ballbagbagins]

These run into this rats nest which goes behind the clocks.

[ballbagbagins]

And also to this fuse box, specifically the red cable with the black tape on.



The red cable next to it is for the dash cam which is staying.

[ballbagbagins]

There are two lots of cables behind the head unit. The bunch on the left are the ones in use. The lot on the right must have been used for a previous head unit.

[ballbagbagins]

I'm thinking of removing all the wiring for the previous head unit. Does anyone know what these two wires might be doing?
One end disappears under these relays in the driver's footwell, the other us in the bunch of wires for the previous head unit.

[Rich]

Jul 2, 2023 16:17:23 GMT ballbagbagins said:

There are two lots of cables behind the head unit. The bunch on the left are the ones in use. The lot on the left must have been used for a previous head unit.

The wiring on the left is the factory radio wiring. The mess on the right all needs to be traced and removed unless the speakers are all now being ran off an external amp or something. That’s a right old mess needing all tracing and removing. I’ve seen some very odd faults caused by bad radio wiring in VW cars, even had one that was causing a CANBUS over-run and making the EML come on as the ECU couldn’t communicate with other modules.

[ballbagbagins]

Removed almost all of the wiring for the previous head unit.




One wire I have left in place is this one that connects to the back of the instrument cluster. Any ideas why this ran to the old head unit?

[Rich]

CANBUS speed dependant volume perhaps?

[squonk]

Backlights on the stereo that only come on when the instrument lights are on? Which pin does it go to on the ISO connector? If its on connector A pin 6 thats what it is.

[ballbagbagins]

Jul 5, 2023 22:44:54 GMT squonk said:

Backlights on the stereo that only come on when the instrument lights are on? Which pin does it go to on the ISO connector? If its on connector A pin 6 thats what it is.

Thanks for that information.

I can't remove the iso connector so can't see what pin. Can I just leave it alone or should I remove the wire?

[squonk]

What is the white connector that you are holding?