2024 TGE, replace oem split charge with b2b

[californiatime]

Hi Everyone. I have a 2024 TGE with OEM 2nd battery under the bonnet.

I want to replace the split charge relay (OEM) with a victron Orion XS 50 b2b charger.

Seems simple in my head, can I just check my workings:

1) remove existing split charge relay under the bonnet, put Orion XS in it's place (so feed into it, then output to battery). Connect earth on Orion to chassis or battery negative.

2) What do I do to get the Orion to switch on/off? Do I use the cable that BCM cable that connects to the split charge or do I use smart settings in the Orion? And if so, is it configured right from the factory or do I need to adjust something in the BCM (I have VCDS). Clearly don't want any smart alternator / euro6 nonsense playing into it working properly! Just want it to charge when engine running, and not when it's not !

Thanks

 

[rod_vw]

I would use the wire from the BCM which according to my wiring diagram should be a 1sqmm Red/White. That way is more correct than connecting the XS to an ignition switched signal that most of us have to do with as accessing the BCM to add the OEM signal wire.

 

[californiatime]

Brilliant, that sounds straightforward. On my aux battery there is a BCM/sensor of some description on the negative pole. Do I leave this connected as-is? I presume so as does it just tell the BCM to turn the relay on/off (the 1mm red/white wire) based on the state of charge of the aux battery? Or do I unplug it? I seem to remember somewhere that if you unplug it the van defaults to thinking it's at 50% constantly, thus switching on/triggering the relay.

Finally, I assume the alternator will just do whatever it needs to do to cope with all this going on, and it won't lead to me having a flat starter battery?!

 

[rod_vw]

Hi @californiatime if you are fitting a Orion XS to manage the charging of your leisure battery I think it should not have the old leisure battery monitor included. However I don't know how you should remove it from the vehicle coding. It's my understanding that the battery monitor that is fitted to the OEM second battery -ve terminal manages the alternator output to ensure the correct charge of that battery but in your case you have fitted the XS to do that. Maybe @mmi will come onboard with this discussion and can help you.
Sorry @mmi to bring you into this but it's beyond my knowledge.

 

[Scottish Scrutineer]

I’d contact Roger Ivy at Off Grid Solutions for advice.

 

[mmi]

Please post
(1) full VCDS Auto-Scan
(2) Adaptation map of BCM (09)
(3) Adaptation map of Special Function control unit (3D)

 

[californiatime]

Please post
(1) full VCDS Auto-Scan
(2) Adaptation map of BCM (09)
(3) Adaptation map of Special Function control unit (3D)

Will do - just need 10 mins to myself to get out to the van!

 

[californiatime]

Hi @mmi

Here you go - as requested. Thanks in advance for your help.

 

[mmi]

In the BCM (09) adaptation map there is a mention about second battery charging - but marked as not installed.


Obviously because the aux battery charging is controlled by unit 3D-Special vehicle control unit. Below a snippet from Crafter workshop manual - "Factory installed accessories and conversions"

Couldn't find anything obvious in adaptation map of 3D-Special vehicle control unit. Possibly something useful in coding?


1 - Dash panel insert -KX2-
2 - CAN bus wire
3 - Special vehicle control unit -J608-
4 - E-LIN bus wire 2
5 - Battery monitor control unit 2 -J934-
6 - Second battery
7 - Electrical system connection for body builder
8 - Second battery charging circuit relay -J713-
9 - Alternator
10 - Battery
11 - Battery monitor control unit -J367-
12 - E-LIN bus wire 1
13 - Data bus diagnostic interface -J533- (19-CAN Gateway)

---

Below a function description found in the workshop manual:

1.4 Notes on function of second battery charging circuit relay -J713-

Switching states of second battery charging circuit relay -J713-
♦ Closed when engine is running safely and there is no energy-critical condition.
♦ Closed when external charging is detected with engine not running.
♦ Open with engine running and energy recovery active, when charge level of second battery is more than 90 % and only low current flows.
♦ Open when engine is not running or when engine start-stop system is in stop mode.
♦ Open for a period of one minute when external charging is detected with engine not running and ignition switched on.
♦ Open at engine start

 

[californiatime]

Thanks, v helpful. Will take a look at coding options for the special vehicle control unit and see what’s there.

The third bullet point on the operating functions could mean that the b2b I’d replace the split charge with would switch off without the batteries being at 100% and going into float. I wonder what state the svcm puts the charger output into if I disconnected the 2nd battery monitor control unit?

 

[rod_vw]

@mmi rarely fails to come up with the goods, thank you.