Switched live power…

[Grubscrew]

Thought I’d share with you a switched live power supply , like say you want to put Fog lights in via a relay. I did just that , but having contacted a VW in a main town, I was told “ splice it in from another circuit….really.?
So after a little bit of “digging” I found a spare switched live in the bank of fuses . Big blue circle is the sub bank , then the green one is the 10 amp fuse to the relay.
VW do make a factory kit, but these lights as some of you know will need programming in to the ecu.
This bank of fuses is under the passenger seat.
Just thought it may help someone.

 

[Oldrat]

That’s useful, thanks.
Ripe for a piggy back fuse take off

 

[Raul a/3]

That’s where I picked my signal for the dc dc charger. And there’s another one near by, comes life as you switch the ignition off, and back off when ignition is life. I gues it was prepared for the California conversion to cut power off when you drive.

 

[rod_vw]

The way that VW control the split charge for an auxiliary battery is by a connection from the Onboard Supply Module (Pin T73c/72) and is coded in that module. That connection activates a simple high current relay (J713). Diagrams available if anyone wants them.

I've not got around to doing the electrics on the TGE yet but the above info is from the Crafter/TGE wiring diagrams.

I've used that method on a T5 but have a B2B in the T6 which senses the point that the alternator charges without an additional wire.

 

[ralphwireless new VW]

The way that VW control the split charge for an auxiliary battery is by a connection from the Onboard Supply Module (Pin T73c/72) and is coded in that module. That connection activates a simple high current relay (J713). Diagrams available if anyone wants them.

I've not got around to doing the electrics on the TGE yet but the above info is from the Crafter/TGE wiring diagrams.

I've used that method on a T5 but have a B2B in the T6 which senses the point that the alternator charges without an additional wire.

Is there a schematic for the Crafters? Mine is brand spanking 2024

 

[elliott]

That’s where I picked my signal for the dc dc charger. And there’s another one near by, comes life as you switch the ignition off, and back off when ignition is life. I gues it was prepared for the California conversion to cut power off when you drive.

I need to pick someone's brains on this. I want my dc to dc charger to come on when ignition is live. Need help identifying where the ignition live terminal or fuse is? And would I wire my charger from start batt? Any help would be great. Also I'm running a 160ah battery, would a 40amp dc charger be sufficient?

 

[rod_vw]

I need to pick someone's brains on this. I want my dc to dc charger to come on when ignition is live. Need help identifying where the ignition live terminal or fuse is? And would I wire my charger from start batt? Any help would be great. Also I'm running a 160ah battery, would a 40amp dc charger be sufficient?

Have you looked at the picture at the top of this thread, the fuse allocation is shown there. I've added a piggy back fuse like this for my ignition live wire to the B2B.

Fusing of the link between the starter battery and your B2B depends on the version of your B2B. Don't forget to fuse it at both ends and use cable of sufficient cross sectional area (sq mm). Look here for advice on cable size here but be aware that chart/calculation refers to 'round trip' cabling, if you are connecting the chassis ground by the leisure battery then enter half the starter to B2B length plus half the chassis ground length into their on-line calculator.

 

[elliott]

Have you looked at the picture at the top of this thread, the fuse allocation is shown there. I've added a piggy back fuse like this for my ignition live wire to the B2B.

Fusing of the link between the starter battery and your B2B depends on the version of your B2B. Don't forget to fuse it at both ends and use cable of sufficient cross sectional area (sq mm). Look here for advice on cable size here but be aware that chart/calculation refers to 'round trip' cabling, if you are connecting the chassis ground by the leisure battery then enter half the starter to B2B length plus half the chassis ground length into their on-line calculator.

Yes thanks for the advice. I'll be using a renogy b2b 40amp. If I need more help I'm sure you can help. Really appreciate It rod_vw

 

[rod_vw]

Yes thanks for the advice. I'll be using a renogy b2b 40amp. If I need more help I'm sure you can help. Really appreciate It rod_vw

@elliott I have used 16sq mm cable from the battery under the front floor (fused at this end) to my leisure battery location in the rear left corner of the vehicle, it's fused again just before the B2B. Because my installation was originally done by my converter and I have now upped the B2B to a 50A I am hoping that 16sq mm will be OK, it looks like it on the calculation page that I linked you to. I know that is touch & go with a single estimated length of 3.75m (on the 12v Planet page showing 'The voltage drop is 3.94% (0.473 volts'). I'll keep an eye on the charging figures and can always drop the charge current on my B2B a small amount. Remember mine is a LWB TGE.
My -ve (chassis ground) is run to the earth stud on the left chassis rail near the rear spring mounting.

 

[madfazer]

The solution to make your 12v sockets ignition actuvated is to remove the blue wire with black stripe from its original position circled in turquoise above to it new location circled in yellow above. Carefully pry the connector out and re insert into th new location then re install 20A fuse in new location. You now have ignition activated 12v sockets. Hope this helps.