range rover p38 1995 air surspension advice needed

hi all about 2 weeks ago while going down motorway for some unknown reason I felt I had lost lift ( never had a problem before) vehicle was recovered to local garage they have don't a diagnostics and data test they found faults on ecu and air suspension module faulty the module has been replaced the ecu been replaced all errors have cleared data test is saying car is functioning good but car will still not lift is there somethink that I havn`t done ie reset the air compressor is ok please if any one has any idea please advise
many thanks
karl

Do you have "Hard fault?". If yes and you have "35mph" message then system needs reset using diagnostics or RSW software on a lap top
Worth having a read of Wammers guide in the Technical Section at top of page

I havn`t had any messages come on dashboard im being told now there are no faults recorded after these items have been replaced is it possible the compressor pump could be working but not pumping enough air to lift car

Lift the compressor out. Three 8mm nuts.
Undo the blue pipe, 12mm spanner and start the car up. The compressor should blow your finger off the output, if not the seal has worn inside the pump. The ecu will wait for a certain amount of time for the vehicle to lift when asked. If it doesn't react it'll go into fault mode and drop to the bump stops and shout about it. Check the compressor for a good air output.

ktjclc said:

I havn`t had any messages come on dashboard im being told now there are no faults recorded after these items have been replaced is it possible the compressor pump could be working but not pumping enough air to lift car

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The EAS ECU almost never fails. If the car is not lifting, it could be a hard fault which should give an error message, or a leak which could be an airspring, an air line or the valve block or even a blown fuse.
You can check the compressor using Wammers guide in the tech archive.
The garage have just replaced things without any idea what they are doing.
The only answer is diagnostics

+1^

Worth checking the EAS relay located under the passenger seat behind the trim

Datatek said:

The EAS ECU almost never fails. If the car is not lifting, it could be a hard fault which should give an error message, or a leak which could be an airspring, an air line or the valve block or even a blown fuse.
You can check the compressor using Wammers guide in the tech archive.
The garage have just replaced things without any idea what they are doing.
The only answer is diagnostics

Click to expand...

+2.

Check Wammers post in the Technical Section and follow it through.

And another vote here for Wammers technical guide. If not for this logical testing regime and more than a bit of common sense from the lads on here I'd still be driving on the bump stops!

Grrrrrr said:

+2.

Check Wammers post in the Technical Section and follow it through.

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+3 I always say Check wammers technical post. I keep a copy in my owners handbook