L322 2006 3.0TD6 Suspension issue

Hi folks, I’m having a problem with my RR suspension. Any information most welcome.
Current Situation is as follows;

1. RR is sat on the bump stops
2. Won’t lift
3. Suspension fault message on the dashboard
4. Orange Lights on control panel for raising and lowering are both lit at the same time however they both go off a few seconds after the engine is started.
5. Have to clear fault code for them to come back on again.
6. Fuse 57 is ok
7. Just fitted a brand new compressor and new air tank
8. Replaced relay(old one since tested and proved serviceable)
9. New compressor was changed because I had filling slowly error and overheating messages and eventually it stopped working altogether.
10. New compressor won’t start. (Plug and play same unit as old one)
11. Using HawkEye total, one fault code showing DTC: C1A29 Switch activity’s taking too long.

Not sure where to go from here but many thanks in advance for any assistance.

Sounds like the compressor is feeding a leak.

Thanks for your reply. Unfortunately it’s not starting up, so not feeding anything, at least a leak would be easier to resolve.

diverivor said:

Thanks for your reply. Unfortunately it’s not starting up, so not feeding anything, at least a leak would be easier to resolve.

Click to expand...

It will not start if there is a hard fault present and it may already be toast if it has been feeding a leak.

Hi, the new unit hasn’t started up at all, it’s the old one that’s toast. I’ve bench ran the new unit prior to installing and it performed fine but for some reason it’s not being triggered to start.

diverivor said:

Hi, the new unit hasn’t started up at all, it’s the old one that’s toast. I’ve bench ran the new unit prior to installing and it performed fine but for some reason it’s not being triggered to start.

Click to expand...

Have you cleared the faults? I don't know a lot about the L322, but turning the steering lock to lock clears some problems.

Hi, yes cleared the fault, that’s when both lights on the control panel (raise and lower) lit up and only stayed on for a few seconds then no lights and no compressor starting up. Also did the steering full lock both ways.
Not sure if the control module is toast.

Maybe one for @Saint.V8 , no lights means its gone into hard fault for whatever reason.

Many thanks will contact, got to sort it.

@Saint.V8 might pop up now I have tagged him.

The pump will not run until you have cleared the hard fault

biketeacherdave said:

The pump will not run until you have cleared the hard fault

Click to expand...

Many thanks will keep looking.

Can you post a picture of your height selector lights....you say both the raising and lowering lights are both on then go off....I am not sure which lights you mean....as the height selector switch panel has lights for each of the ride heights, and a light on the inhibit switch.

Many thanks for replying. Please see the attachment photo.

Ahhhh....it is not raise and lower lights, the top is Off Road height, and the bottom is Access Height....

When two ride heights lamps are lit, one is usually steady, and the other (the new selected height) flashes until that height is reached, which it then goes steady, and the previous steady light switches off...

If they are both on steady...and then go out, this could indicate an ECU issue, as when all lights go out, this indicates a system hard fault. It is located up the passenger (UK) side of the dash on the A pillar...it's location means it can get damp in certain circumstances.

Best to pop it off and check the connections to it aren't corroded or damaged, or the unit isn't wet.

The fact diagnostics says something akin to switch fault - it may even be an issue with the ride height selector switch itself....whilst this is mostly unheard of - it is at the end of the day a mechanical switch and things can go wrong...and this would one of the first times i have heard of this.....not sure how much s/h switches are, but it may be a case of getting one and giving it a go if it isn't to expensive!

So, first off check the ECU connections...then try a known good height selector switch...if both of these fail to resolve the issue, try a known good EAS ECU.

Thanks for your advice , I picked up a ride height selector control switch from eBay and installed it today but the results stayed the same, however it was worth the £15 just to rule out a faulty switch and at least I have now have a spare clock and switch panel.
I will investigate the EAS ECU in the morning and see what’s happening with it. It seems quite a coincidence that the issues occurred at the same time as the change of the compressor and air reservoir.
Ps. Battery and alternator tested ok today. I’ll let you know how I get on.
Regards diverivor

Does your diagnostics tell you tank pressure?

Is there air in the tank?

Saint.V8 said:

Does your diagnostics tell you tank pressure?

Is there air in the tank?

Click to expand...

Morning Ant, busy man these days. Hope you and yours are keeping well and coping with the lock down.

Hi gents, no compressed air in the brand new reservoir as compressor hasn’t fired up yet. I have a HawkeyeTotal which will tell me live data, (just read 96kPA,that’s equal to atmospheric pressure ). I will remove AS module and clean up contacts as Saint.V8 recommend then check live data again. To try and make total sense of what’s going on there are 79 live readings, so to be as accurate as possible I will list them. You gents will see exactly what’s going on, so please bare with me.
Regards diverivor

Hi gents, regarding air suspension module, there’s no sign of water issues and the contacts are all clean and the pins are straight. Please see added pictures. With that it would probably make sense to have it tested whilst its out.Are these units coded to my vehicle or can I just buy another unit and plug it in ?