While driving along the other day in me '99 P39 4.6 my suspension decided to do something funny.

It was a bit of a rough stretch of road, was bouncing a wee bit, and went round a roundabout a bit faster than I should, and may have bumped out [I think the front shocks are gone, but that's another project]

Anyway... EAS starts blinking as if switching to fording mode. I can hear the compressor running, and after it had been flashing for about a minute I thought I would crap out and forced it back to standard mode via the switch.

It's done it once more since then. I can't find the manual telling me why or when it would automatically switch to fording mode; or am I missing something?

Jock

Hi.
When you say "fording mode" do you mean the highest setting?

Cheers, Nick.

Yes, the highest setting. Did it again today, but this time while I was sitting in the driveway.... oh b**locks. Compressor running, highest mode flashing (with standard setting still lit) but when I moved off it returned to normal.

Did it suddenly change to high mode or did you get in, start the engine and the normal light was lit but the high mode light was flashing??

If you drop it down to motorway mode or access does it raise back up quickly or pretty slowly??

-Wills

The first time (on the bumpy road) it just switched. High mode started flashing and after it didn't cancel, I cancelled in manually.

But today, I had started the rangey and it was in normal mode initially. It was idling while I fitted the car seat (doors open) and then when I got in, the high mode was flashing and I could hear the compressor running.

When I reversed out of the drive, it returned to normal mode on its own.

Jock

BigJock2007 said:

The first time (on the bumpy road) it just switched. High mode started flashing and after it didn't cancel, I cancelled in manually.

But today, I had started the rangey and it was in normal mode initially. It was idling while I fitted the car seat (doors open) and then when I got in, the high mode was flashing and I could hear the compressor running.

When I reversed out of the drive, it returned to normal mode on its own.

Jock

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Was the high mode flashing OR just solidly on and was it flashing while the doors were OPEN?? Not doubting what you said, just trying to make sure

I have to say, I just climbed in, shut the doors and then realised the light was flashing. Whether it started flashing before this, I can't tell. Trying to remember, I think it was once I closed the doors and got ready to move off.

It clearly doesn't sound like something common or obvious to you then?

BigJock2007 said:

I have to say, I just climbed in, shut the doors and then realised the light was flashing. Whether it started flashing before this, I can't tell. Trying to remember, I think it was once I closed the doors and got ready to move off.

It clearly doesn't sound like something common or obvious to you then?

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Well, if the high mode light is flashing when its in high mode then I usually get that if I have had it in high mode and unloaded alot of weight from the vehicle. The height sensors see the car raise and the flashing orange high mode light indicates that the EAS is in extended mode (this is a mode that is designed to get you out of trouble should you bottom out on something, it raises the car even higher than high mode).

If it happpens again take note BEFORE you shut the doors and see whether its flashing or solid.

From your description the car was in normal height mode when you started you then got out, left the doors open, loaded in the car seat and then got back in to find the height sign flashing?? It sounds possibly like a faulty height sensor HOWEVER i would of expected a soft EAS fault if you had that. You havent had any sort of fault have you that cleared once you restarted the engine??

Have you tried changing height like I suggested earlier?? Does it lower to motorway or access mode fine and then come back up quickly?? Or once you are in motorway/access mode and you try and raise it does the new selected height light just keep flashing for a long time and you slowly rise?? Do you know when the compressor was last replaced?? Have you ever done any work on it yourself??

-Wills

Well, thanks for the comments. What you say about the soft fault makes sense.

It works fine otherwise, it goes into motorway mode automatically, and it comes back out okay. If I leave the doors open for a period (I tend to start it, then load in all the crap I'm taking) it goes into low mode as well.

Today I got another interesting one though. I put the inhibit mode on to see if it would inhibit motorway mode, but it had no effect.

I've only had the machine 4 weeks, so still discovering its foibles. So far I am extremely happy, but I don't read many compliments about the air suspension - other than it gives good ride quality.

I've done no work on it yet. It's due a 6,000 service, and since I've just bought it I will probably do plugs, filters and fluids myself. I think it also needs brake pads, as there's too much movement in the pedal and I got a low fluid warning once on a very steep hill. According to the manual the pads seem like the easiest I've seen, although I'm sure a problem or two will expand the job by a couple of hours.

I will be out and about tomorrow - will let you know if it starts doing the "mind of its own" thing again!

Jock

BigJock2007 said:

It works fine otherwise, it goes into motorway mode automatically, and it comes back out okay. If I leave the doors open for a period (I tend to start it, then load in all the crap I'm taking) it goes into low mode as well.

Today I got another interesting one though. I put the inhibit mode on to see if it would inhibit motorway mode, but it had no effect.

I've only had the machine 4 weeks, so still discovering its foibles. So far I am extremely happy, but I don't read many compliments about the air suspension - other than it gives good ride quality.

I will be out and about tomorrow - will let you know if it starts doing the "mind of its own" thing again!

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Have you tried changing the heights when sitting in the driveway just idling. Height changes should be smooth and pretty quick - less than around 7-10 seconds between heights. If the change takes any longer and the selected height light is constantly blinking and the compressor running then you have probably got a worn compressor which you can refurbish.

The going into low mode once you have started the vehicle and loaded it up is normalish. What happens is you start the car, it levels or is probably level at normal height. You then go and load lots of weight in the back and the whole car gets heavier so the height is changed and when you get back in you will likely see two lights lit up on the EAS panel. Most likely the normal height mode and then the motorway mode. If you just drive off the system just picks the lower level as far as I know (it always has for me). If you dont drive off you can just push the height change button to 'remind' it of what height it sgould be at and it should change within seconds.

As for the inhibit switch - that doesnt sound right. If you are in normal ride height and have the inhibit button pressed the heights should not change AT ALL unless you tell it to, it will only self level. When the inhibit switch isnt used car with drop to motorway mode at 50mph or above when that speed is held for over 30 secs. It will then come back up to normal height once the speed drops below 30 (might be 35, cant remember) mph for over 30 secs.

Does the height inhibit switch light up at all when you press it?? A test you can do to check the inhibit switch is working it to drop the car down to access mode. Once there put the vehicle in P (or neutral if its a manual), handbrake on and foot off brake and then press the inhibit switch. You should get a beep from the dash and a message saying EAS Manual on the message centre. This would allow you to drive in access mode upto 25mph. However the point is if you do get the message then your inhibit switch sounds like its ok. If so try going back into normal height, press the inhibit switch and then drive at over 50mph for 30 secs and see if the vehicle height changes at all.

-Wills

Cheers Wills, will try the inhibit test you suggested. The light comes on, but it switched down to motorway mode at about 60 all the same.

The other things you suggest could explain alot as I typically climb in and out fixing to child seats while it's idling, and it does rock about quite a bit. Maybe not do that any more.

I will also test the height change in the driveway and see how it performs.

Jock

Okay, did tests and there seems to be only one problem.

Sitting in the driveway, I changed the ride height to highest. It lifted up in about 4-5 seconds, followed by a minor adjustment and everthing was fine. I selected the lowest, and it lowered in about the same time, maybe a couple of seconds more. The lights on the dash indicated appropriately.

I pressed the imhibit and then steamed onto the motorway. At about 70, I took off the inhibit and it went straight into motorway mode. So I think I have been hallucinating about that one.

That leaves only one "problem". It does, I would say once each day, select highest mode off its own back. BUT - I think (and it's difficult to check this with the wife and kids in the car) it's when I go round a roundabout with a bit too much enthusiasm, and it happened at one tricky 90 degree bend also.

What makes the highest mode engage? Is it when you hit a bump stop? Or is it just when the EAS picks up excessive movement? I think my shocks are worn and the vehicle might be rolling too much. Could that engage it?

And by the way - the compressor doesn't continue to run, it just runs for a short while. However, the EAS light on the dash remains lit when its in high mode.

Jock

BigJock2007 said:

What makes the highest mode engage? Is it when you hit a bump stop? Or is it just when the EAS picks up excessive movement? I think my shocks are worn and the vehicle might be rolling too much. Could that engage it?

And by the way - the compressor doesn't continue to run, it just runs for a short while. However, the EAS light on the dash remains lit when its in high mode.

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Okkkk, high mode should ONLY engage when you ask the vehicle to rise up there. It can get engaged if you have a heavy load in the vehicle and then unload it. Also, during the night you can loose height not only due to the fact the vehicle self levels but due to the fact of the outside air temp, as it gets colder the vehicle can drop as the air inside the bags cools and it can also go the other way and sometimes rise a little if its a very warm night.

Either way this doesnt seem to be the problem, I would personally lean towards the faulty height sensor(s) even though you havent had a fault I would get them checked - you can do this yourself if you feel confident getting under the vehicle, removing them and have a good multi-meter. Otherwise I would say goto a good specialist and not a dealer and let them have a look at it for you, they can hook their Rovacom or similar system upto the vehicle and check the sensors that way.

If you think you have worn shocks then I would get them replaced as this could be a factor in the problem although I doubt it. Worn shocks will present themselves by allowing the vehicle to bounce up and down over and over after going over a bump - not only that when I had worn shocks mine made a kind of rubbing/squelching sound which drove me nuts and that alone made me replace the buggers!! I suppose if they were very worn and were allowing excessive movement then that might cause EAS problems - either way if you suspect they are gone get them changed and see what happens. You can always get the EAS checked at the same time

Let us know how you get on...

-Wills