I am looking at workshop manual and it says to use the points under the bonnet.
It then says to turn the ignition on but do not start the vehicle.

Is that the way to charge? Do I need to leave the ignition switched on? Won't that add stress to the charger? How does this step work?

Also, will it charge the main and the aux battery?

Thanks.

That seems inconsistent with the owner's manual, at least going by ownerinfo.landrover.com for my model year. If you want to connect a trickle charger the easiest thing if you have tow electrics is to get an adaptor from the forum shop and plug the charger into the adaptor with the adaptor in the tow electrics. That worked well for me during the lockdown.

There seemed nothing about switching on the ignition until actually ready to start the car in the instructions for use of a donor vehicle and jump leads, or a starting aid device.

I don't know about the second battery, sorry. Only Range Rovers since 1988

I've hard wired a CTEK connector to the under bonnet posts.

https://www.fullfatrr.com/forum/topic48040.html

SO my car has dual battery system. This is what I am reading:

procedure covers operating instructions for the following battery support units;
Traction BSU2-50 / 125
Fronius ACCTIVA Professional Flash
MIdtronics CX-Pro 50
Traction MPL-50
Midtronics PSC 700S
WARNING: Make sure that the cables are
connected in the correct order.
NOTES:
This Step contains connection instructions for the
following vehicles;
LG / L405
LW / L494
Connect the battery support unit positive cable
to the jump start positive terminal.
Connect the battery support unit ground cable to
the jump start ground terminal.


Then:
CAUTION: The Traction Showroom Support Unit
(SSU2) must not be used during diagnostic sessions.
Only the Traction Battery Support Unit (BSU) / (BSU2)
can be used.
NOTE: This Step contains operating instructions for
the Traction BSU2-50 / 125 battery support unit.
NOTE: Switch off any auxiliary systems,
for example: headlamps, to reduce the electrical
load on the battery support unit.
Switch the ignition ON, but do not start the engine.
NOTE: Confirm that all 3 lights are
illuminated green before starting a diagnostic
session.
Switch ON the battery support unit.
The battery support unit is now ready for a
diagnostic session.
NOTE:

Anyone know if applying charge the post under the bonnet charges both the Aux and Primary battery?

I am reading that one should never directly charge the battery in vehicle and disconnecting any battery will throw a lot of codes and needs Range Rover tool to fix.

Jack this is for the workshop when diagnostics are being used sir... There must be a suitable battery tender/charger attached when software upgrades etc are performed, for obvious reasons

NOT for end users sir

You charge both batteries from the front post yes sir...

Thanks Cam-tech for clearing it up.

Do I need to keep the ignition on (engine not started) for charging both the batteries?





Looking at this diagram shows that aux battery is isolated if ignition is off ? I am reading that Aux is for sensitive electronics and remains isolated when cranking and stop/start?

Item
NOTE: A = Primary battery supply; B = Secondary battery supply.
Description
1 Tandem Solenoid Starter (TSS) motor
2 Generator
3 Primary battery
4 Power and engine management system loads
5 Power Supply Distribution Box (PSDB)
6 Battery 1 connection on Power Supply Distribution Box - disconnected
7 Battery 2 connection on Power Supply Distribution Box - connected
8 Secondary or auxiliary battery
9 Sensitive loads

No sir you do NOT want the ign on... It will turn itself off after just a few minutes anyhow!

The key will be how that power distribution box works.

It could be ignition controlled switches, or it could be voltage sensitive (more likely).

My boat has dual batteries with a VSR (Voltage Sensitive Relay) - that below 12v disconnects the 2 batteries and above 13v connects them. So at rest they are disconnected and under charge are connected. They connect when being charged by the alternator or on a plug in charger.

I have no idea whether the L405 is VSR or ignition controlled, but expect VSR is more likely.

Thanks Cam-Tech, Alistair.

Do you know what should be voltage at the posts under the bonnet to confirm battery is charged?