Alternator feed (D+) location for split charging system

[Pidea]

I've got a 56-plate Auto Roller 600G motorhome that's based on a Ford Transit chasis with four wheels on the rear axle.

It has a factory installed split charging system that I suspect has failed as the voltage across the leisure battery doesn't change whether the engine is on or not.

My understanding of how split charging system works is that the alternator needs to send a signal via the D+ (?) wire to the split charging system.

I'd like to confirm that this is happening but the fusebox for the interior is unlabeled so I'm trying to find the wire from the alternator to it. I'd also like to check the various fuseboxes. So far, there haven't been any blown fuses in the three (one under the bonnet, two behind glovebox) but there's always the possiblity that there's a fuse missing.

Where should I look for the D+ feed under the bonnet and where would it enter the cab ?

Thanks in advance

[MinorMatt]

Is it a late mk6 or an early mk7?

Assume its a 2.4?

[Pidea]

Apologies for the slow reply - I didn't get a notification of your reply.

According to the V5 it's a 2.4 diesel and it's an early Mk7. It was registered on February 1st 2007

Phil

[Altransit]

Apologies for the slow reply - I didn't get a notification of your reply.

The forum doesn't notify replies (by default) unless you tick that box in your 'profile', or alternatively, you can tick the "subscribe topic" box when you post your message