Cold should not affect it considering it is -35C with the wind chill here and mine works fine. Damp conditions do effect it. Sometimes my Nav screen will go white and I will loose sound in all front speakers. This has happened lots of times but as the car dries out everything returns to normal. If it is the DSP I would just replace the head unit with aftermarket and redo the speaker wiring to suit.

OK I found the issue after a lot of work on the truck on the weekend.
First red flag of the procedure is it took 10 depressurizing cycles to get the truck down near bump stops. I had to remove the pipes to get it down all the way.
I replaced the valve block with a unit I bought off eBay and rebuilt. At first the compressor seemed to run forever so I knew I had issues. Off I went to get the soap and water spray. I found no leaks but discovered the previous owner of the valve block had mixed up the solenoids. Crap, depressurize!
Ding ding round two after checking all the wiring on the valve block. Truck rises but compressor does not shut off. Red flag number two. Checked for leaks and nothing. Compressor is still going. Getting hot so I pulled the relay.
After some head scratching I got the idea to check the dryer for a blockage as it seemed to have an issue getting air out and into the system. Dryer was done. Rock hard. New drier being ordered but I did find some desiccant to use in the mean time so I can keep truckin.
I have to rebuild the compressor again as it was being fried trying to push air past the block of desiccant in the dryer.

I was not under the impression one could locate the screws incorrectly. One set of holes goes through the base and one does not? One set of screws are countersunk and one set is recessed. I will look at it after replacing the valve block tomorrow.

When I was having issues on mine cleaning the connectors was not enough. I got some dielectric grease and applied to to all pins. No light since.

You can check the sensors at the ECU connector. Check Rave for the pinouts.
You can replace the sensor with used ones but you will need to re calibrate the EAS after. If you have never done it you can swap the sensors from side to side to get a new wipe on the tracks internally. I can't do this due to the bolts and salty roads in winter.

I'm just going to wait for the replacement to get here. This is a picture of the exhaust solenoid that is in there. I think when it cracked it shifted sideways and bent the valve below causing the plunger to stick when operated.
I would rather a truck that won't go down than one that won't rise! lol nothing sexual intended!

Hey Gordon. I am by no means an expert on this system and frankly I feel like pouring petrol on the ** thing. I suspect my exhaust valve is causing most of my issues but I don't have a spare to swap. This is what I think is happening.

1. ECU opens both front solenoids and Exhaust solenoid (Only plunger is stuck or solenoid does not operate?)
2. Air is forced past rear plungers into rear bags.
3. ECU thinks front has lowered and opens rear solenoids and Exhaust solenoid (Only plunger is stuck or solenoid does not operate?)
4. Truck freezes with ass in the air and dash lights flashing.
5. Ecu thinks its stuck and raises to extended.
   The symptoms described in my last post are probably a mix of both Diaphragm and Exhaust solenoids failing. I have a used block on the way to rebuild and drop in.

So I put my old Diaphragm Solenoid back on for testing purposes. After a while it failed and these are the symptoms for anyone down the road.

1. EAS tries to lower and fails as diaphragm is closed blocking exhaust exit.
2. Air is diverted from front springs to rear spring because of weight of engine.
3. Rear Height sensors register 130 or more while the fronts register 70 making the ECU think the truck is stuck.
4. ECU requested Extended Pro and compressor activates. Compressor proceeds to fill the rear bags even more.
   I had to pull the compressor relay to prevent any issues with the air springs as they registered 156 or higher.
   I used Nanocom to level the truck and pulled the timer relay.
   The height switch lights flashed for Extended height and standard height at the same time. If I clicked standard it would return after a second to both flashing again but the truck did not move. I'm still learning about the system so I could be wrong about some stuff.

So I was busy on the weekend and dug into the EAS system again.
Diaphragm replaced with old one solid disc design that does not leak.
Checked the check valves and all were installed correctly with zero lube.
Checked all wiring from the ECU to valve block. All tested good.
Found the reason the door trigger did not work. Corroded splice between the ECU, Timer Relay and BECM.
Found a leak on one of the lines from the air spring. Fixed.
Found I have 2 slow punctures on the front of the truck. Getting these fixed this week. One looses 5 Psi over night.
Found the Exhaust solenoid is cracked and possibly sticking.
I did a full calibration of the heights. They were very close to where they should have been. 3 bits out max.
The compressor no longer short cycles.

So the following symptoms persist even though I have very close to the magic carpet experience again.

1. When I was raising the truck using EAS unlock suite the air was being blown out the exhaust rather than to the spring. This happened a couple of times and then after I clicked lower and back to raise it worked fine. Sticking solenoid?.
2. When the compressor stops. Sometimes the blow off does not happen for a second or two. Sticking solenoid?

I order a used valve block and compressor off ebay today so I will have spares in a week.
I also order a rebuild kit for both. I plan on rebuilding the whole box when it arrives and drop it into my truck.
I also plan on testing the height sensors this weekend for dead spots.
Thanks for following my insanity!

Door trigger works for everything but EAS. Also Park brake trigger for EAS does not work. On Nanocom it show park brake off and door closed no matter what I do. I am looking into all this on the week end.

I just found a post stating exactly what you have said. Thank you for confirming it.
List for the weekend include.
Check wiring from ECU to Driver unit.
Calibrate using blocks. I made some 4 years ago.
Get front left tire fixed. Slow puncture which apparently will affect the EAS.
I had replaced 2 bad height sensors with used units.
Yes it works with Nanocom as it should.

It does not fall to earth. As the compressor runs the rear of the truck rises above standard (could be the whole truck as I just noticed in the rear mirror using the lines on the glass as reference) when compressor stops truck returns to standard height and starts again. With the timer relay removed the truck still rises gradually. I have to insert the relay to bring it down. No lube on check valves. I had already replaced a worn out one.
Nanocom will move the truck to any height I select. The EAS works at all heights as designed. Tank fills in just under 10 minutes while raising the truck to first height setting as door trigger does not work. EAS thinks doors are always closed. Located in Ontario, Canada.

dazer2000 wrote:

This may be a long shot mate but check the wiring from the underseat base through the passenger side kick plate / sill gaurd, i had lots of issues with my old p38 with suspension and thats why the previous owner sold it as he could not get it sorted anywhere, I did valve block drivers pipes pump etc and it still played up so I looked further (3 months of investigations) I were new to p38 so had fresh eyes to learn with and I set about wiring issues and found that because the footwell gets damp from peoples feet and the wiring under there that there were a number of wires corroded inside the plastic, I rewired them all ( some around 1 foots worth) and all was fine ever after and all worked good.
Worth a look.

I redid the connectors in the foot well but I am going to dig deeper into the wiring in this area as with Canadian Winters it gets very wet. Thank you.

Thanks for posting blueplasticsoulman
Just so you are up to date on this saga the following parts have been replaced or repaired.
Compressor rebuilt
Valve block rebuilt 3 times
Driver unit replaced with new unit.
Connectors in left foot well repaired
Electrical connectors in EAS box dismantled, cleaned and tightened.
Compressor Relay
All 4 Air Springs
Diaphragm Solenoid
Dryer Unit
Zero Leaks that I can find external to the block.

The system fell back into full retard mode last night. I had to disable again. If I enable the system the rear of the truck rises while the compressor is on and the drops after the compressor stops and the the cycle continues until the compressor fries itself. Thankfully I caught it before this happened. Also the truck rises when the EAS is disabled so something weird is going on for sure. If I took saved the live data from nanocom would you be able to decipher it? I don't know how to get the info I need from the data.

Video of odd noise from valveblock exhaust. https://www.youtube.com/watch?v=p9ZX6nVdlgI

I rebuilt the valve block on the weekend and replaced the Diaphragm Solenoid as the blue wires were cracked and corroded at the solenoid. It is behaving better but not completely normal. I have never actually got the EAS to work 100% in the 5 years I have owned the truck so to be able to drive the truck without disabling it is a bonus for now. There is a minor leak from the exaust while the compressor is on. The diaphragm is new. ¯_(ツ)_/¯

My compressor is running on/off all the time. I have the compressor cycle going on where the truck rises when the comp is on and drops after it comp stops etc..... forever! EAS is disabled until I can rip the valve block out again. NRV's are leaking slightly. Always have. Replaced with used ones and had no change. NRV's are always installed dry. The EAS on this truck has driven my completely insane at times and runs smooth other times. Valve block driver unit was replaced with new unit.

yes it was installed dry. I had the same issue as blueplasticsoulman last time with a failure. I am thinking it has happened again. X8r diaphragms suck!

Would an bad diaphragm solenoid cause it? I get some air out the exhaust while compressor is on. Just replaced the diaphragm.

What problem could allow the truck to rise when commanded to drain the air bags by the nanocom evolution? i.e. I told the nanocom to drain the rear bags and the solenoids clicked continuously as the truck got higher. The bags did drain but only completely drained after the second attempt with the nanocom.
A symptom I have right now is when I lower the truck it takes forever to actually lower on the rear. The front lowers rather quick. The solenoid clicks rather than just opening to drain the bags.

I have a set of blocks I made from dowel but lack a level surface to use them. Guess I need to borrow a garage floor.