Hello and thank you all for the many posts I've read concerning a DTC c2302.
Here's my problem, car ( 2006 xj8 ) has the 2302 code, which comes on every drive in about 2-3 min.
Things I've done.
Rebuilt compressor and changed fuse and relay.
Checked all connections air and wires.
No leaks found, car sits fine for days even with valve block unplugged.
Done the battery off then leads held together.
While driving I can watch my scanner and see compressor come on and off (only runs for about 20secs or so) also see leveling come on . So it's trying to level the car and I am thinking it can't thus the code.
Here is my question, should there be any air pressure in the line between the compressor and the valve block, when parked and not running? I don't think so.
I was going to let the air out of the system and restart it all and the first line I unconnected was the compressor to valve block ( white ) and there is a small amount of air escaping from the valve block side.. I suspect a faulty solenoid in the block not closing all the way. As it sits I'll see if it's from a bag or tank.
Also what should the pressure in the tank read and does the sensor read tank pressure or system pressure. My readings vary, highest I've seen is about 145psi sits at 104 a lot.
Scanner I use is a Autel MS909
Thanks again

 

If the system is unable to level the car I would do the following:

Inspect every level sensor and wiring for damage on the vehicle.

Remove the sensor (easy) and connect multimeter reading ohms

Move sensor lever and ensure reading changes smoothly.

The pressures you quote seem low.

Search suspension technical data for figures

BTW are you in Australia?

 

There are two codes with numbers very close together, (1) C2302 Levelling plausibility error, and (2) C2303 Reservoir plausibility error. If you have a levelling problem you could have a faulty vehicle height sensor. For a 2006 car there are two on the rear, one per side, and one on the front, (not sure which side). From what you've told us, my money is on the height sensors

 

Thanks for the replies and yes the code is 2302 leveling plausibility. I have inspected the three sensors and the wiring they all look good. I will ohm them to check their movement and reading for smoothness.
While the compressor line was off the valve block, the block was leaking air back, this was coming from the left rear bag solenoid as that bag slowly deflated, and the right rear dropped a little. this tells me the valve block is bad, I believe all solenoids should be closed. The leaked stopped when that bag was empty and the tank still had pressure in it. Because it leaked back to the compressor it couldn't escape unless the exhaust solenoid opens. this is why the car never sagged over time. Interesting though the sensor I had suspected is the left rear. I have a valve block coming tomorrow so I'll install it and see what happens. If that doesn't fix it I'll remove the sensors and ohm them. Are there error codes for the sensors? I have watched their movement thru my scanner and the left rear numbers always seamed off to me compared to the right rear. Of course I'm not sure what the numbers should be. I could be wrong about any part of this so I appreciate your inputs.
No I'm in Washington state, Seattle area. Thanks again.

 

No error codes specific to the sensors, i don't think. The data stream should show measured height at each sensor; i know my tool could report that.

 

Thanks again for the replies, here's what is going on now. I replaced the valve block and the old one/original had corrosion in a couple of the holes so I know it was bad or at least was going out. But did it solve my 2302 no.
An interesting observation while all air lines were off the block the front did not sag at all, the back went all the way down. I did read that there is a pressure retaining valve in the bag to keep a min pressure but they barely dropped. Should the front stay up so much?
Also the ride height of the front is about 40mm above the spec. ( spec = 386, mine is 425! )
Rear height is also a bit high at 390 with spec. at 373mm. Although the car sits level to the eye. I think it's too high.
I agree it's most likely a height sensor , so I did ohm test them with kind of strange results.
Front sensor had no movement on the meter.
I got movement on the rear sensors but my connections were not great. sometimes moved sometimes not.
Reassembled all and checked thru the live data on the scanner. all three sensors show movements either pushing on the car or driving down the road.
The rear sensors numbers do not match but both move consistently, one much lower than the other ( left rear being lower all the time).
Even though the numbers for the rear sensors are not the same I don't see the system trying to raise that bag while leveling is on.
Could the front but stuck in a default (high) position if the sensor is bad? therefore the system can't level it self? And why would the scanner show it moving?
I think the front is bad because it never changes and has always looked and measured high.
One of the rear sensors could be bad but which one? The higher or the lower ? Visually the rear of the car looks correct not too high, not low.
Just for info this car has 180000mi and the front bags were replaced about 6-10 months ago.
Thanks

 

Update 2302 solved ( ?? )
I decided since the car was too high in the front to let out the air a bit to see if it would level up correctly.
The fittings on the front bags have that PRV on top of the bag just under the actual air line inlet. So if you only loosen the air line the bag wouldn't drop I had to also loosen the fitting under it then down it goes.
I didn't let all the air out just enough to drop the front down closer to spec.
Took it for a drive while watching the scanner. the leveling came on a couple of times the compressor a couple of times then all quiet, no errors! Pulled over put in park level would come on for a moment the off still no errors.
The front end number is a lot lower and i was able to drive for a while. the leveling never came back on while driving like it did before ( when I would get the code ).
Back in shop and the front height is now 390mm ( spec 386 ) the rear is about 376 ( spec 373 ) I'd call that ok.
I think the initial problem was the valve block, then somehow the front got over inflated. That PRV wouldn't let out enough air to drop the front (crazy) so, no level thus 2302.
The sensors seam to work fine and even the rear sensors are closer now.
We'll see if it stays good, thanks for all your help.