I have an 07 LR3 and I am pretty sure there is a leak in my system but I havent had time to find it and it wasnt causing any real issues that I could tell. Now when the suspension fault message comes on the light on the dash is red (used to be yellow), it tells me to drive 30mph max and the back tires fall all the way to the bumpers in a minute or so and I can hear the compressor clicking but not running as if it were trying to reinflate the rear struts. I turn the truck off and back on and it will reset and fill the suspension to normal ride height but after about 5-10 minutes it fails again. Will the compressor continue to pump air into the system above 30mph? If the compressor wont work at a certain speed then it seems obvious that the back is leaking fairly rapidly and once the compressor cant function the back end just empties out. Then again, when the truck sits turned off in my driveway the back end does not drop down at all. Will the compressor engage and keep it pumped up even if the car is off? I know it self levels when the car is off but I thought it only let out air to level it and that it would not add air while its turned off. When I stop the truck and turn it off the back suspension lets out a quick release of air, I assume this is just leveling itself but I am not positive about that. Also, the last clue is that my wife manually lowered the back end with the switch inside the car on accident and then drove it about 2 miles with no suspension active and that is when the problem began. Could that have damaged the valve block in the back? I am an amateur mechanic and this whole system is new to me. I tired to provide as much information as I know about what is going on in hopes it will give someone a clue as to what I should do next. Last question, is it more common for the valve block to fail or the actual air struts? Thanks for any advice and help!

 

System will not inflate while driving, at least the compressor will not turn on to inflate. That is why when you restart it inflates.

If it's not losing height while parked overnight sounds like to you have a height sensor or compressor issue.

All of this is useless talk unless you get a GAP tool to read codes or take to a garage that can read codes.

Buy a GAP tool and report back.

 

My money is on a calibration problem (cross-articulation fault) but the fact that the fault "used to be yellow" makes me think the compressor could also be on its way out....agree with Abran, get an IIDTool by GAP.

 

With further testing I am almost positive it is the valve block in the back. It only fails when I get up to highway speeds and when its cold. Yesterday during the day it worked fine but then this morning it failed again. When I get the error message on the dash I got out immediatly and could hear the valve releasing air in small spurts until the back end fell down completely. I am not certain the valve block is to blame and will get the joys of replacing that.

 

It's a cross-articulation fault. If you lived near Seattle I'd bet you a beer on it, and then drive over with my IIDTool.