Gilbertd wrote:

You've got a leak somewhere. Pull fuse 44 (pre-99) or 29 (99 or later) and leave it overnight. That will show you which corner is leaking and dropping. Then you will need to get the soapy water spray out and check the air springs, connections to the air springs and where the pipe comes out of the valve block for bubbles.

I assume that disables the entire system, including the checks triggered by the door switches?

Craggle wrote:

What, the pump runs every 20 - 30 minutes with the ignition off and parked up?

Sagging suspension overnight is normally air leaks. Air springs get perished or the valve block seals get old.

Craig.

The compressor only runs when driving with the Inhibit switch pressed. The sagging is overnight, ignition off, Inhibit switch still pressed.

The air springs were absolutely buggered when we got it two years ago. God knows how it passed the MoT they gave it at the dealer. They are all new.

Car is low mileage at 68k and garaged for most of its life, but I guess standing can do as much harm as high mileage.

Having successfully fixed the over temp sensor in my car (photos soon) we realised my wife's car has an issue.

Even with the inhibit switch pressed with the height set to Standard her compressor is running every 20-30 minutes and the car sags right overnight.

What are the first things to check in order of probability?

I was thinking mainly in terms of reliability. A cluster of things in the EAS have gone wrong of late. This seemed a likely candidate, Down there in the salt!

It is handy that failure is open, giving the option of piggy backing a new one. Thanks for the help. I was a bit down about this whole thing as the car was just back on the road. I was excited and on my way to a track day for a ride in a 440BHP M3, so this hurt. There's another opportunity at Thruxton on Tuesday and I found a 3rd pump in the workshop with a working sensor I can cannibalise

The light at the end of the tunnel is back on ... might be a train though!

Do people refurbish these or buy an off the shelf alternative? A lightweight corrosion resistant composite would be nice. Fittings are standardised, aren't they?

I'm planning a Viair upgrade next month. I seem to have several choices: 350C, 380C and 444C. I gather Marty's is outside the original box I'd like to put it inside.
Which would be the best fit?

Okay. Definitely going Viair but skint at the moment.

Does anyone have a link to the pictures and tips for replacing the over temp sensor in the compressor?
I found a couple and it's a mess in there. Motor brushes exploding all over the place. Do you switch the sensor or the entire board?

I had already ordered from the eBay link but he's away and can't post until tomorrow. That's why I was hoping to get one from RS. I suspect the photo on eBay has been doctored to remove the numbers. I'll post here when it arrives.

Found the sensors on RS but there are 4 with no clue which to pick. 12v obv. Closed when cold. But what temperature?

https://uk.rs-online.com/web/c/switches/industrial-switches/thermostatic-switches/

Both ideas noted. But things have moved on.

Switched back to new ECU.

1 Noticed some corroded pins on the old one I missed the first time because my work light is a bit directional.

2 Ran the pump for a minute with the Nanocom just to prove a point. Cycling through the INPUTS I saw Temp Sensor was showing HOT. Checked the pump - cold to the touch.

It was showing NORMAL earlier. I should keep a log because I'm not 100 percent sure which ECU I had in.

Thermistor in order. Arriving Monday.

Honestly, though. I'd rather get a Viair, ground the Orange wire and never go through this again. I know purists disapprove of this kind of thing, but with a duty cycle of 100 percent (not 15) and almost 4 times the flow rate it seems perfect. Some people worry about demand spikes at startup but anecdotally that doesn't seem to be an issue.

My current hypothesis is that the ECU in the car is faulty.

The new ECU appeared faulty but actually threw an error because it's calibrated for a different car and the values were out of range.

I'm going to give it a fair crack of the whip buy reconnecting it then doing all the crap with the plastic rods. All without a working pump... Trolly Jack and my arms will take a hammering.

I assume running the pump with Nanocom does so with exhaust valve open so I can't cheat? Thigh it occurs to me jumping the relay might work as long as i monitor the pump so it doesn't overheat.

I also wonder if just copying the Access mode figures might be enough to kick-start things...

Gilbertd wrote:

About the only thing left that you haven't checked would be the pressure switch. If the pump needs to run it would be open circuit, closed when the system is up to pressure.

I have a Nanocom. Anything else I can check?

"Raise Switch" and "Lower Switch" both say OPEN.

Car is in Accss.

These values do not change if I select Standard.

What are they? Where are they? What does it mean if both are OPEN?

C141 Pins 7 and 9 open.

Testing:

Orange and black wires are connected.
Maxi Fuse 2 intact.
Relay 2 works in Syckes-Pickavant tester.
Removing relay and jumping 3 and 5 runs pump.
ECU switch for another LRPN: ANR4499

Three of them hold up the kick panel under the glove box.

Replacing ABS sensor (front right}.

1 HTF do you pull it out?

2 How do you squeeze both buttons on the plug at the other end?

3 Two lower clips have dissolved. Are there part numbers and are they still available?

Cheers!

Found this. Driver's side in front of the battery.

It's very clean so seems to have been plugged in until recently. Wires are white\purple and black\purple.

Any ideas?

Perfect. Thank you very much.