Another basic ambulance electrics question

[andytw]

Hi,

Really starting at ground level here. 1997 Transit converted to an ambulance and then converted to a camper.
Bit of a panic.

So looking under the bonnet I have 2 batteries left and right.
The right hand battery has a big red isolator which, from a previous post, we have established is a self latching isolator for the right hand battery.
Inside the vehicle by the drivers knee is a small red turn isolator switch with removable key

I am faced with a vehicle with flat batteries and non operation of starter solenoid when jumped.

Need to know :-

Which is the vehicle battery left or right.
Are the 2 batteries strapped electrically together, depending on operation of the red isolator next to the drivers knee.It appears that may be the case.
Where might I find earth straps.

I think the leisure or auxilliary is the one on the right.
I am going to set it's isolator to 'off' and then remove it
Then work on the vehicle with a good battery in the left position and then work on getting it cranking over.

Any info at all appreciated

Just editing this.
Sorry for gabbling on

It appears to me that :-

The right hand battery may be the main battery
The left hand battery only gets connected across the right hand battery when the the isolator by the drivers knee is turned on.
Could this be a reserve battery function for jumpstarting ???? Basically you end up with two batteries in parallel.

The big red switch on the right hand side basically switches both negative and positive to the vehicle, so for ANYTHING to happen AT ALL this switch needs to be on.

[andytw]

Making sense of it all. The non cranking was the starter. New starter fitted.
Looks like one not very good battery and one totally U/S battery.