Range Rover Sport Suspension Issue

[BMKal]

A friend has just been around with his 2010 Range Rover Sport. Over the Easter break, he had a flat right rear tyre. He jacked the right rear corner of the car up via the recommended LR procedure, and had to jack the body that high that the suspension was "super extended". Once he got it back on the ground, the back suspension levelled out at something like offroad height both sides, and has since risen to fully extended (I've never seen LR suspension this high). At the moment, the rear is "super extended" and the front appears to be at about normal offroad height (when compared to my Disco 4 parked next to it). I connected my Gap tool to his car and attempted to clear all the faults (there were many) and to lower / deflate the suspension. Could hear a "click" from somewhere near the compressor when I tried to deflate the suspension, but nothing happened - if anything, the rear rose slightly higher. We have tried everything that my Gap tool would allow (his car is not licenced to my Gap tool), and have tried everything with the normal suspension controls, including driving the car at higher than 50 km/hr (he is getting continual warnings that he is travelling too fast and the suspension is about to lower, but it still will not lower.

Looking at the angle of the rear suspension sensor arms, they are at about 45° (mine are not far from horizontal at offroad height). My suspicion is that the rear suspension sensors have moved too far and gone "out of range" causing the ecu to fault, and I am thinking of taking off the "rods" from the rear sensor arms so that I can manually move the sensors back into range.

Has anybody experienced this before and know any tricks to fix it ? I seem to recall having read about this happening before, but have searched this forum and elsewhere and cannot find anything that helps.

Cheers ....... BM

[Graeme]

I assume that the raise and lower LEDs aren't flashing because off-road height has been tried.

Check that the height sensor arm hasn't gone past vertical and flipped the wrong way, not that it should be able to do so.

[PerthDisco]

Could always try to use Gap tool to deflate all corners then re-enable EAS then clear faults.

[BMKal]

I assume that the raise and lower LEDs aren't flashing because off-road height has been tried.

Check that the height sensor arm hasn't gone past vertical and flipped the wrong way, not that it should be able to do so.

Raise and lower button has no effect. Also, there is a message on the dash that all terrain modes are unavailable.
The height sensor arms have moved much further than mine (I raised mine to off road height so that we could compare) but they have not gone past vertical.

[BMKal]

Could always try to use Gap tool to deflate all corners then re-enable EAS then clear faults.

Tried that. All that happens is that you can hear a "click" when I push the button to either deflate corners, deflate reservoir or deflate all. Gap program comes back with the message (after some time) that procedure was successful, but nothing happened. If anything, the rear actually raised slightly when doing this. Car certainly looks higher at the back than when it arrived at my place, and the numbers on the suspension screen on the Gap program (assume they are heights) have increased from just over 150 to just over 160 (both rears) - the numbers for the front are about 48.

[Graeme]

Is the compressor in the same spot as the D3/D4 or in the bottom of the boot under the spare wheel? If under the spare wheel then the compressor may be the same or similar to those fitted to the L322 which have a brass silencer on the exhaust line which becomes blocked, requring a small drill to make the hole larger. Even if in the same spot as the D3/D4, it may still have the brass silencer being a Range Rover.

[PerthDisco]

Have you tried driving very slowly and then activating the lower command. I have seen previously that motion is needed to calibrate.

[Graeme]

I see that it is the same as the D4 and has the same exhaust silencer as the D4 which doesn't get blocked like the L322 silencers.
It still seems like an exhaust issue but only for the rear, suggesting a blocked rear valve block or reservoir valve block.

[BMKal]

Have you tried driving very slowly and then activating the lower command. I have seen previously that motion is needed to calibrate.

Yes - tried lowering when the car is moving to no effect. The car also displays the warning that it is about to lower when he drives it over 50 km/hr but nothing happens - just the continual warning.

[BMKal]

I see that it is the same as the D4 and has the same exhaust silencer as the D4 which doesn't get blocked like the L322 silencers.
It still seems like an exhaust issue but only for the rear, suggesting a blocked rear valve block or reservoir valve block.

Thanks Graeme. I had a good phone discussion with Mike (Tombie) last night and he also believes it is a blocked exhaust valve. Have a bit of a plan on how to lower it by cracking an air supply line with the vehicle sitting on stands under the chassis rail. Need to check whether it is a Hitachi or AMK compressor as likelihood seems to be a failed dessicant problem (especially if it is a Hitachi which, given that it's a 2010 is more than likely).

I have a 2011 Disco and it's also possible that mine has a Hitachi compressor - will pull the cover plate off mine today and check, and if it is a Hitachi, will order a service kit for mine as well (good to have the spare parts on hand for when I eventually have similar problem).

[Graeme]

The heavier front could be lower than the rear due to pressures having equalised if the system exhaust (compressor exhaust or exhaust pilot valve) is blocked, rather than a blockage on the rear valve block.

[Tombie]

The heavier front could be lower than the rear due to pressures having equalised if the system exhaust (compressor exhaust or exhaust pilot valve) is blocked, rather than a blockage on the rear valve block.

Given the vehicle cannot even execute the purge commands for the tank or front, I'm leaning towards the main exhaust being the culprit

[BradC]

Should be able to disconnect the gallery to compressor hose then and when "lowering" it'll just vent the gallery to ambient. That'll tell you if it's the exhaust valve or something else (not that I can think of anything else it could be). If you can drop the car then plugging it all back in should allow it to raise to normal height. You could then pull the fuse and wait for the service kit.