2012 LR4 Reluctant to lower from off-road suspension mode

[jackkyxu]

may I ask what is a normal working status for the compressor?


should it run every time car is ignited or every day to top off the reservoir (like very short duration of working)?



sometimes when I turn off the engine and lock the car, I can see car lowered immediately , sometime I do not see, is it normal?

 

[Longtrail]

As I mentioned in the other post, mine runs shortly after cold start and then as needed. The car will level itself every two hours when not running (which is why there are threads when diagnosing overnight dropping issues that talk about removing the fuse in the engine bay). Other than this the compressor will run when the reservoir gets below a certain pressure; not sure what that pressure is but I'm guessing it's in this forum somewhere (and also possibly in this thread as I know I charted some pressures in the past).

 

[Roastbeef]

@Longtrail I registered just to say a big THANK YOU for documenting all this - I've been chasing the same problem after a compressor swap (with a non-OEM part), found this post, reflashed the compressor firmware using my already-owned GapIID tool, and this morning at 23F it seems to be solved! It was showing up more often on cold mornings, so I was starting to think I had moisture freezing, but I'll bet it's to do with voltages / sensor signals, and cold starts likely lowering the running voltage after startup a bit more.

You saved me a lot of trouble - I hadn't seen any other discussion on the firmware during my initial, only about drilling a hole in the silencer. I was about to start tearing into valve blocks etc much like yourself, and also considering paying the extra $$$ for an AMK compressor.

Interestingly, mine did already say it was flashed as an AMK - but knowing these same compressors were used across BMW and others, I suspect there are slight differences in firmware for each platform.

Anyway, THANKS again for the documentation here, and for solving my problem!

 

[Longtrail]

So glad I was able to help; this is exactly why I try and leave breadcrumbs for others. Knock on wood mine has been working with no issues... I did purchase an AMK compressor and found one for a decent price in the UK, even with the shipping it turned out to be a good deal.

I reckon you could be right about the voltages, my other suspicion was the attitude of the vehicle, so whether it's parked on an incline or not.