Our P550e PHEV has been parked - with the DC level-2 charging cable plugged in - for 5 days. The 38.2kWh PHEV battery is at 100% charging level, but when trying to start the precondition heater through the Remote app, I get a message saying that the vehicle has been put in a "sleeping mode" to save battery, and that I have to start the car to charge it and enable preconditioning again

Does that mean that the built-in Level-2 DC charger does not charge (top-up) the 12V LiFePO4 service battery in addition to the main 38.2kWh PHEV battery? That we have to buy a separate LiFePO4 12V charger to charge the service battery - and connect that charger to the battery-terminals under the bonnet when leaving the vehicle for a few days?

If the built-in DC charger does not top-up the 12v LiFePO4 service battery, how does the L460 charge the 12v service battery when driving the vehicle in pure EV mode for many days in a row? L460 P550e AB SWB MY24
Sold: L322 TDV8 Vogue MY07
Mini Cooper S Convertible

I don't know about the PHEV models specifically but I know mine goes into sleep mode after a number of days without activity to protect the battery even if I've got the CTEK on and I'm unable to use the app for anything until I've unlocked the car with the key then the remote start and preconditioning is available again.

You would have thought the PHEV would recognise its plugged into the mains and not go into sleep mode but I wouldn't be surprised if thats what it is doing. 2021 P400 Silicon Silver AB
Gone 2011 Bournville TDV8 VSE
Gone 2008 Black Canadian HSE LUX

It's just a bit strange that one has to connect an extra charger to charge the start/service LiFePO4 battery in a PHEV vehicle.

Jez: Which CTEK charger are you using? I've understood that the CTEK Lithium XS charger is only able to charge up to 60Ah batteries, but will that be sufficient for the LiFePO4 start battery in the L460? L460 P550e AB SWB MY24
Sold: L322 TDV8 Vogue MY07
Mini Cooper S Convertible

I think this is more down to how the car 'shuts down' and goes into a deeper sleep after, IIRC, 3 days. In the InControl Remote app, you can set the car to 'wake up' on a particular date so pre-conditioning would be available again.

Thanks Autobiography, I now see that one may activate the "Wake up" function within 48 hours after the last use in the Remote app.

So: Hopefully the onboard DC charger is able to charge the LiFePO4 start/service battery in parallel with charging the PHEV battery! L460 P550e AB SWB MY24
Sold: L322 TDV8 Vogue MY07
Mini Cooper S Convertible

Hi Eirik, I use a CTEK MXS 5.0 attached to the front post for times when my vehicle is left for a few of weeks in the garage. Just to stress mine is a P400 petrol though - not a PHEV  2021 P400 Silicon Silver AB
Gone 2011 Bournville TDV8 VSE
Gone 2008 Black Canadian HSE LUX

Jez, my impression was that all L460 are equipped with LiFePO4 start/service batteries, or do the petrol and diesel versions have AGM start/service batteries? L460 P550e AB SWB MY24
Sold: L322 TDV8 Vogue MY07
Mini Cooper S Convertible

jez000 wrote:

Hi Eirik, I use a CTEK MXS 5.0 attached to the front post for times when my vehicle is left for a few of weeks in the garage. Just to stress mine is a P400 petrol though - not a PHEV

Do not use a CTEK MXS on L460/L461!!

For interest, I have left my D350 mild-hybrid on the drive for 6 weeks and it started first time. MY23 D350 HSE
On my 7th RR plus various other JLR vehicles