Freelander 2 Electrics

[PeterC]

Just want to tell my story in case it helps others (and it is therapy for me). My FL2 SD4 2013 original battery died recently and I got a replacement. At the time we were having problems with the car not locking and it took us awhile to work out that the rear door locks and electric windows were not functioning. My mechanic cleared a bunch of codes relating to comms faults and it all seemed good. A few weeks later after not driving the car for 3 days I had a flat battery. I charged it up and had my mechanic check the error codes. He cleared some, but the error "Local interconnection network bus circuit 1" could not be cleared. The rear doors problem also came back. Days later I pulled the fuses out for each door, they were OK, I put them back and everything then worked fine. I assume it reset the modules.

In a fit of paranoia I started monitoring the battery voltage and it was often at 12.2V before starting, so I had the battery checked and they said it was fine and the voltage was normal for Land Rover vehicles which seemed to draw some power when first unlocked etc.. This seems to be true. I fully charged the battery to float then left the car locked and unused for 3 days then plugged the charger in again. It took 8Ahrs of charge before again being full.

Another question while I am here. Does anyone here know why there is a noticeable whining noise coming from the engine when unlocking, opening a door or once engine is off that goes for between 10 seconds and half an hour?

Thanks.

[FisherX]

Hi Pete,

The whining noise is from your throttle body and normal and nothing to worry about.

As far as your electrical issues go, checking for fault codes is where you start the diagnosis and not where you necessarily finish.

For your battery to be dead after 3 days you have a parasitic draw somewhere. You can use a Amp meter on one of your battery cables and it should be reading in the milliamp range with the car off and after about 10 min (when the interior lights go out). I'd expect to see about 200mA if everything is normal. If it's higher than that you can start pulling fuses (and replacing them) one by one until the amp readings drop to normal. When the amp readings drop to normal that is the circuit where the issue is. And i'd bet that is the circuit where you are getting your BUS fault from.

CAN BUS faults usually come from a dodgy module or the CAN BUS wiring, either a short to earth or an open circuit. To track down CAN BUS faults you really need an oscilloscope to check the signals as you spend hours methodically go through the system. Without an oscilloscope you really are just guessing. Our 07 FL2 has 24 modules on the CAN BUS but yours being a MY13 probably has a few more. Maybe time for an Auto electrician to have a look at your car.

Best of luck I hope you get this sorted. Having a flat battery all the time is just a PITA.

*(Just for some info and looking at the wiring diagram and your rear door issue, the rear doors are not on the CAN BUS but are controlled by the front door modules which are. The rear RH door is controlled front RH door module and rear LH controlled by the front LH module).