Dear All,

since purchase of RR 2009 3.6 tdv8 I have being experiencing so called "christmas tree faults": engine fault, suspension off...transmission fault...hdc off and so on. These set of faults happen occasionally, but in chaotic way. RR might catch these set of faults while driving without accelerating, while accelerating easily, while cruising or while slowing down, once a month, once a quarter, 3 times per day. For the last 3 months these of set of faults happened 3 times: while accelerating within the speed range from 20 mph to 35 mph, while driving at 30 mph and slowing down at traffic light and while driving on highway at 70mph on cruise control. After every restart, RR runs perfectly. I have visited today garage to read faults, please results below:

From your description I would look at the very basic things first. Those faults might be sporadic but the general conditions you describe could be something as simple as a bad earth. That "Christmas Tree" scenario is normally because the voltage supplying the various ECUs drops low and causes one or more of the ECUs to reset.

If that was all happening at start up time it would point to low battery voltage during engine cranking. But if the battery connections are not perfect, or if you have an earth strap loose you would get a similar set of symptoms at random times, just as you describe.

Note that this could be any of the earths in the car. If one of them is poor it could be causing problems with a single ECU. The most likely culprits would be the main ECU, possibly the BCM but I would go through as many as I could find ensuring they are clean and tight.

Generally when the transfer box joins in with HDC faults it's power related... normally lack of, caused by duff battery, so a rotten earth connection could be the source..... And I thought that those faults had died with the Defender, looks like Land Rover have retro fitted them to the Range Rover for old time sake  Yesterday I couldn't spell Engineer... Today I are one!
Inventor of the 'Guide-o-Matic automatic wheel alignment tool'
Former long term L322 owner, Up/Down graded to a Classic Tractor!

Thank you very much, appreciate. BTW, battery is newly fitted last winter and occasionally on start the message pops up on screen: reactivated suspension.

as above, the easiest place to start is the battery terminals. Then move to earths.

My 3.6 occasionally they up faults, but after cleaning and tightening the battery it was much better. There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
KIA E-Niro 4+
2021 Discovery 5 D300 MHEV commercial

alangrig wrote:

Thank you very much, appreciate. BTW, battery is newly fitted last winter and occasionally on start the message pops up on screen: reactivated suspension.

The issue is solved: the problem was related in high pressure pump PCV Valve. Indie flushed it away with brake cleaner several times. For the last 3 months no issues so far.
Thanks everyone for support

Photos the pcv valve ?

Dear All,

please accept apology for keep you awaiting for result for so long time. Finally, the low pressure failure in fuel system has been resolved by replace new high pressure fuel pump. This winter the issue became permanent under low temperature, so we could drive our fullfat only with rev up to 2k. Prior to replacement, local Land Rover indie checked all related system that could cause this issue:

1. Fuel horse
2. Fuel pump in a fuel tank
3. Filter grill in a fuel tank

I familiar with the case where Indies from Russia make some life hacks by replacing only PCV (Siemens A2C59506225) or VCV valves on high pressure fuel pump, but in the end in turns out that the whole unit should be replaced.