Dreaded Parasitic Drain (Again sorry)

[NC35]

Hi Everyone,
Bit of a long shot, but here goes...
Before I start taking things to bits anyone seen wires like these behind the glove box.
In its previous ownership it had a tracker fitted and a previous owner seems to have added some stuff too (eg led footwell lights).
This is the wireless that has aroused my suspicions...
Thick black cable.

 

[Dellmassive]

Got some pics of the starter battery connections?

And general electricals in the van?

 

[NC35]

I have just traced the wire back to the starter battery and disconnected this wire.
The draw has dropped instantly to about 40mA
The battery connectors are now completely standard.

 

[NC35]

 

[NC35]

Still a mystery as to what this wire is for.
(Excuse the excessive copper grease...)

 

[roadtripper]

Definitely trace that cable. If it was connected directly to the battery terminal that's a definite nono as the BCM will not track that drain and believe the battery is more charged than it is leading to poor charging.

If you find it's something you need to reinstate find another earth point, the bolt on the bonnet hinge next the battery is a popular option.

Also it looks like there was no fuse in the positive, again not a good idea.

As to what it is maybe they had a dash cam?

 

[DXX]

If you haven’t located both ends of the cable make sure that it’s not connected to a power source at the other end.
Given the state of the terminals I doubt it was installed by somebody with the necessary knowledge. Insulate those terminals just in case.

 

[NC35]

If you haven’t located both ends of the cable make sure that it’s not connected to a power source at the other end.
Given the state of the terminals I doubt it was installed by somebody with the necessary knowledge. Insulate those terminals just in case.

I can confirm there is zero voltage across the disconnected terminals. But good idea, I will wrap them both with insulation tape and cable tie them out of the way.

 

[NC35]

Definitely trace that cable. If it was connected directly to the battery terminal that's a definite nono as the BCM will not track that drain and believe the battery is more charged than it is leading to poor charging.

If you find it's something you need to reinstate find another earth point, the bolt on the bonnet hinge next the battery is a popular option.

Also it looks like there was no fuse in the positive, again not a good idea.

As to what it is maybe they had a dash cam?

All good at the moment. I have noticed anything not working, bonus!
I installed a dash cam (properly I think) with inline fuse and to a switched source on the central fuse panel.

 

[NC35]

So, all quite good this morning.
12.4v after unlocking and opening the van.
But... still quite sluggish to start, it has been like this since I bought the van.
Suppose next steps are seeing if I have a lazy starter motor or failing glow plugs. A job for 2026.
Huge thank you to everyone who took the time to answer.

 

[Howzat]

The easiest thing to test is the battery itself. What's it like after a 20-30 minute run, turn off and start again? Still sluggish? If not then it's 90% new battery time especially with the cold weather now.
Or maybe try a 24 hour charge then check V then leave 4 hours and check V again. It shouldn't drop more than 0.3V in that time and if it does new battery time.