[PXR.1]

if you bridge the compressor relay (remove the relay, there is usually a diagram on the relay identifying the pins on the relay, and place a piece of wire between the two relevant contacts - those that feed 12V to the compressor), then if the compressor runs, it will point to a faulty relay or lack of signal to the relay. If the compressor does not run, then double-check the fuses, as it indicates an absence of power.

Many thanks Arnie65.
I will give that a go.
Assuming I can’t get the compressor to activate (by bridging the relay), do you think I might be able to inflate the bags (by connecting the electric motor terminals to an independent 12v source (with the other power sources connected for the solenoids). If I tried that would I need to have the engine running (to provide power to the three solenoids)?
Thanks again

 

[PXR.1]

Thanks again. I will give that all a go tomorrow. When trying the bridging, would I need to connect the relay socket of 30 with both the 87 relay sockets (or only one of the 87s)?

I do have a multimeter and will try to use that as you suggest but I’m a novice on this stuff! I’ll do some reading up.

I really appreciate your help.

 

[PXR.1]

Many thanks.

 

[PXR.1]

Hi. I was able to bridge the relay. All tubes reconnected. The electric motor starts and runs for a while but then cuts out. No air going to either suspension bag.

I when I disconnected the blue and red pipes no air released (which I assume confirms no air going to bags). I removed the compressor from the car. The chamber was under pressure. I activated the release solenoid to release the air. I then tried to test the two solenoids (the ones that release air to each bag). They looked a bit rusty. Ive used some WD 40 to clean them. I’ve tried to activate them using a separate battery - and to see if I could blow air through them when activated. They remain shut. My suspicion is that there may be a problem with those to two solenoids - but seems odd that they would both go at the same time. Any suggestions as to how I might test if they are faulty?
thanks as always.

 

[PXR.1]

You can test their coils to see if the resistance looks about right (probably around 10 Ohms) and not open circuit or a high value. But this won't tell you if the valve is stuck or corroded, just whether the coil is good.

Thanks. Coil seems good - as I tested a different solenoid in it - and it opens and closes as required. I suspect the two old solenoids are stuck. I tested both in a different coil and neither opened. I know that coil works as it opens up new solenoids.
Regards

 

[PXR.1]

Hi. I was able to bridge the relay. All tubes reconnected. The electric motor starts and runs for a while but then cuts out. No air going to either suspension bag.

I when I disconnected the blue and red pipes no air released (which I assume confirms no air going to bags). I removed the compressor from the car. The chamber was under pressure. I activated the release solenoid to release the air. I then tried to test the two solenoids (the ones that release air to each bag). They looked a bit rusty. Ive used some WD 40 to clean them. I’ve tried to activate them using a separate battery - and to see if I could blow air through them when activated. They remain shut. My suspicion is that there may be a problem with those to two solenoids - but seems odd that they would both go at the same time. Any suggestions as to how I might test if they are faulty?
thanks as always.

By way of update.
I purchased and installed a new compressor. It did not activate when the car was turned on.

I was able to start the new electric compressor motor by bridging the relay. The compressor then runs. However, no air goes to either bag. My, somewhat ignorant, view is that I have deeper problems than just a sketchy compressor.

1. It seems that whatever informs the relay to kick in is not activating/sending a message. I can only activate the relay by bridging it.
2. Even with the new compressor running (by bridging the relay), the second set of solenoids are not opening (to allow the compressed air along the pipes to the two air bags).

Any ideas or suggestions most welcome?

I recognise that I may need to call a mobile electrical mechanic to carry out an electrical diagnoses - but I thought there was no harm in asking this (clearly very knowledgeable) community.

Thanks as always.

 

[PXR.1]

I know that, should the compressor fail in an MB, you can wedge some chocks into the suspension frame to keep driving. maybe there's a simialr method for yor car so that you can drive it to a workshop, as i think this will be more effective than a mobile mechanic.

If you have two working solenoid valves, can you not swap out your old valves with the new ones ?

The air suspension system use a number of sensors to detemine when and if to run the compressor, these include potentiometers on drop-links that inform the ride height. You really need a diagnostic scanner to find the reported fault codes. Otherwise, it's just guess work,

Thanks. I did temporarily install the new compressor, with all new solenoids. It would start, if I bridged the relay - but no bag inflation. I think as both you suggest it needs a diagnostic toot attached to it.

 

[PXR.1]

If the module is detecting a problem it will inhibit compressor operation so if it’s detected a problem with solenoids it’s quite possible it has locked out.
The solenoids are probably corroded inside if the drier pack was previously wet.
where are you located as someone local may have ista to plug in for you, if you was local to me I would certainly plug mine in for you.

Thank you. Even with a new compressor attached I.e with all new solenoids operating, the car would not raise. I think an electrical diagnosis is required. You kindly offer to plug in your ista. I’m Midlands based - just outside Birmingham. You local to there?

 

[PXR.1]

I used to be but not anymore I am south west based. Hopefully someone will chip in and be able to assist

Hi. might it be worth my buying a diagnostic device? One that I might use to see the error codes and, if needed, get the system to activate the pump to inflate the bags (even just to get me to a garage)? If you think that might be an option, do you know what sort of device I should buy?

thanks.

 

[PXR.1]

Air now in suspension airbags.
By way of update.
I have, by hook and by crook, managed to get some air in the two airbags - sufficient to get me to a garage.

For whatever reason the car was not sending a signal to either (1) the relay (to start the compressor), or (2) the two solenoids (those that open to allow air into the two bags).
My short term solution, if it of any help to others, was this:-

1. I installed the compressor back under the car. I connected all the pipes and cables (except for the electrical connection to the two solenoids that open to allow air to the bags). I return to this below.
2. I connected wires to the two positive pins on the dual solenoids plug. I connected a further one to the negative pin.
3. I had a spare 12v battery to hand.
4. I started the car.
5. I then, at at the same time, pinched the relay (to start the compressor) and connected the two live wires from the dual solenoids to my spare battery and the third cable to the negative.

The compressor ran, the dual solenoids both opened. The car then started to rise!

I now need to get the car to a garage to have a diagnostic test run on it - as clearly there is some significant underlying issue. However, at least I know that I have a dried out and fully functional compressor and the 3 solenoids (all bough new) work.

Many thanks to those who have assisted me.

 

[PXR.1]

If the solenoids opened when applying power and comp also runs when applying power it would appear the module is at fault as a guess.
Can’t recall where exactly the module lives in f11 the old e61 it was in spare wheel well and was a favourite for water damage killing them

Many thanks. The module lives near the fuses in the boot of the estate. I had a quick look at that. It was dry and looks clean and in good order - but you may well be right that it is the issue. Once I have had the car into the garage I will let you know what they say.

 

[PXR.1]

Any update PXR.1 as my car is currently undergoing all what your car has gone through. What did you find out at the garage? Mine will raise when the diagnostic computer is used to raise it but it won't raise at the same time as it cuts out but when done independently it raises the airbags but comes down as soon as engine is turned off. I have changed the outlet solenoid valve, the dessicant chamber and beads are dry but only thing I have not tried is order a new relay. Also I think the contributor that said it may also be indicative of a low battery may have a point as I am getting that message on the dash too. That said, I have not been able to drive the car since it dropped on chassis in June. I do run the engine sitting periodically though. Any views?

hi.At the first garage the diagnostic machine stated “transport mode active”. That sometimes is an indication that the car battery is old. However, I have replaced the car battery a couple of years earlier and she knew that wasn’t a problem. No error codes were found. It was suggested I go to a garage that specialises in BMWs. They found a loose electrical connection to the release solenoid. Once that was reconnected, they found no error codes. the suspension now races and falls successfully. I showed the mechanic my old relay switch. He said it it had certainly burnt out and I’ve done the right thing to replace it. It seems odd that your car drops when the engine turns off. Have you found out where the air is being released from? Is that from the release solenoid? Is it from the air bags? Is it from the tubes to the airbags, is it from somewhere else on the compressor?
good luck.

 

[PXR.1]

To be honest, I don't know where the leak is coming from or if there was indeed a leak but my guess is, it is the compressor unit. Well, I have replaced the air bags and a new relay but still sits deadpan on the chassis. I ordered a new compressor too but I was sent one not compatible with my car. The funny thing though is, when I was under the car taking out the compressor, I noticed F07 on the panel plate however, my car log book says F11. Also when I put the identity code from the old compressor to order parts, it comes up with F11. Has anyone ever had the same issues or observation? Anyway, that's beside the point.

I have ordered a new block valve which I will install on the old compressor to see if that works pending the replacement for the one not compatible arrives.
I am just hoping that after installing either the new block valve or new compressor, I won't experience what you went through despite you installing everything new. Thank you for reply.

Good luck with it all.

 

[PXR.1]

Hello PXR.1, I am finally happy my suspension issues resolved today. I ordered a new compressor from Germany and as soon as I fitted it, my car chassis function restored! This is after a course of diagnostic treatments from changing the outlet solenoid valve, then the intake solenoid valve,, new air springs and then ordering new relay but nothing worked until I changed the whole compressor. It has been a journey of knowledge and learning which, without the good input and advice from fellow Bimmer owners here, I would still be in the wilderness over my car chassis issues. Thank you!

Great to know you got it sorted. Whilst it must be a little frustrating that you ended up having to buy a new compressor - it was, as you say, a learning experience. Cheers.