P38A 97 P38 Gems - EAS issue which seems to have expanded

In normal operation, the pressure switch signals the ECU the tank is lower than 120psi, so the ECU triggers the relay. This starts the compressor & closes the diaphragm valve. If yours runs & stops that implies the pressure switch is closing, which can be seen on Nanocom. (Not sure if RSW shows this).

With relay bypass the pump will run continuously, even if the pressure switch closes to signal the ECU. Check for 12V or 0V on pin-9 of C152/C141.

If you connected the 12V wrong way round there's a possibility you fried the driver pack.

I assume the car is still on the bump-stops ??
1) If so, I suggest you reconnect the plugs & compressor relay.
2) Then disconnect the bag airlines at the valve block
3) Start the car and see if the system is trying to send air to the airbags ? (you will hear it immediately)

Remember if the tank has sufficient air, the system will start with two rear solenoids plus the inlet solenoid to raise the rear.

Also start looking for a spare valve block with driver pack on eBay, etc. just in case.

If compressor only runs on diag or by jumping the relay then thermal switch almost certainly fried. Can be fixed quite cheaply if you're careful.

Grrrrrr said:

If compressor only runs on diag or by jumping the relay then thermal switch almost certainly fried. Can be fixed quite cheaply if you're careful.

Click to expand...

With all that jumping and mentions of smoke, who knows what has been fried. It only take micro seconds to destroy semiconductors.

Well lake is delayed a week -
But before I forget I will write this up and then go back to your guys notes...

So things work allot better when not reverse wired.
So followed the program -
Relay jumped compressor for tank pressure - ran it for 6 mins - nice and smooth barely even warmed up
- how long should decent pressure take?

jumped C141 as prescribed.
First step power - one could hear something operating in EAS box - when alligator clip hit the batt terminal
Second step - rear bag inflation - jumpers already in place just connect power. holy creaking rubber (been on bumps for like 6 months now)
Took it up to about normal running height to conserve tank -(wheel well about 38mm above rubber) both came up even - disconnected power
Third step - front bags - switched jumpers and powered up - started to rise but then I heard a low hiss out of front left I will assume bag as it was well below EAS box
But was raising evenly - shut it down to repressurize tank.

Now here is where I didn't know what can stay attached / powered when moving to something else.
I wanted to jump compressor to restore tank - so removed power sources from jumpers but left them in place as I wanted to go back and repeat.

Now this time when I jump relay the compressor is making a couple revolutions then ejecting air in puffs through exhaust.
Ran it for a minute to see if it would correct and didn't.
( Now it has done this before and same sequence of actions to correct)
Restored relay - started up Rover - C152 / 141 still open. Compressor makes a couple revolutions one puff of air and then nothing.

Reconnected 152 / 141 ran engine - compressor didnt start - the EAS red dash light was off - then back on four lights just stayed flashing
EAS fault came up on dash information - hasn't been doing that lately just the slow 55km bit

Turn off engine - go back to jump relay and it operates as expected ran it for 5 - 6 minutes.
Its like when fully reconnected or when I leave it for a couple days -and run it, it reboots its self.


Didnt have opportunity to repeat - people needed me for something. And my window of opportunity was gone before it was supposed to storm - which it did.
But ran RSW same repeated three faults LF, RF, RR signal incorrect
But there was now decent air in rear bags - some in front bags - though RR HS not in place - still waiting on a new HS
I'd like to know what RSW - signal incorrect means or choices / possibilities?
Cleared faults and RSW screen said cleared but being cleared but it didnt show up on log.

Pressure switch closing does not apparently show up on RSW.
I didnt get the Nano as it was single vin - and didn't think there were so many subtilties in the EAS

So depending on weather tomorrow - will get some soapy water to identify air leak around front bag.
And will check air lines at EAS box

Will see about another 141 jump sequence but start at front.

And then double check how you check compressor for continuity etc

Thx - Cheers,

frozen north 2 said:

I didnt get the Nano as it was single vin - and didn't think there were so many subtilties in the EAS

Click to expand...

A Nanocom is not tied to a single VIN but for P38 you buy a code for either GEMS or Motronic or Diesel but it will then work for all GEMS etc.

How long does it take for decent air? Depends how empty the reservoir tank was. The EAS pump isn't designed for big volumes but small volumes at high pressures. To fill the tank from empty will take 5 to 10 minutes. Topping up between height changes maybe 30 seconds.

frozen north 2 said:

Well lake is delayed a week -
But before I forget I will write this up and then go back to your guys notes...

So things work allot better when not reverse wired.
So followed the program -
Relay jumped compressor for tank pressure - ran it for 6 mins - nice and smooth barely even warmed up
- how long should decent pressure take?

jumped C141 as prescribed.
First step power - one could hear something operating in EAS box - when alligator clip hit the batt terminal
Second step - rear bag inflation - jumpers already in place just connect power. holy creaking rubber (been on bumps for like 6 months now)
Took it up to about normal running height to conserve tank -(wheel well about 38mm above rubber) both came up even - disconnected power
Third step - front bags - switched jumpers and powered up - started to rise but then I heard a low hiss out of front left I will assume bag as it was well below EAS box
But was raising evenly - shut it down to repressurize tank.

Now here is where I didn't know what can stay attached / powered when moving to something else.
I wanted to jump compressor to restore tank - so removed power sources from jumpers but left them in place as I wanted to go back and repeat.

Now this time when I jump relay the compressor is making a couple revolutions then ejecting air in puffs through exhaust.
Ran it for a minute to see if it would correct and didn't.
( Now it has done this before and same sequence of actions to correct)
Restored relay - started up Rover - C152 / 141 still open. Compressor makes a couple revolutions one puff of air and then nothing.

Reconnected 152 / 141 ran engine - compressor didnt start - the EAS red dash light was off - then back on four lights just stayed flashing
EAS fault came up on dash information - hasn't been doing that lately just the slow 55km bit

Turn off engine - go back to jump relay and it operates as expected ran it for 5 - 6 minutes.
Its like when fully reconnected or when I leave it for a couple days -and run it, it reboots its self.


Didnt have opportunity to repeat - people needed me for something. And my window of opportunity was gone before it was supposed to storm - which it did.
But ran RSW same repeated three faults LF, RF, RR signal incorrect
But there was now decent air in rear bags - some in front bags - though RR HS not in place - still waiting on a new HS
I'd like to know what RSW - signal incorrect means or choices / possibilities?
Cleared faults and RSW screen said cleared but being cleared but it didnt show up on log.

Pressure switch closing does not apparently show up on RSW.
I didnt get the Nano as it was single vin - and didn't think there were so many subtilties in the EAS

So depending on weather tomorrow - will get some soapy water to identify air leak around front bag.
And will check air lines at EAS box

Will see about another 141 jump sequence but start at front.

And then double check how you check compressor for continuity etc

Thx - Cheers,

Click to expand...

You have succeeded in turning a minor leaking airbag problem into a really complicated exercise.

Sounds like you have an intermittent thermal switch in the pump. If the switch itself is ok, it can be the crimp on the PCB inside the pump. It's possible to fool the ECU by grounding the wire in the connector. Depending on the faults stored the ECU may not run the pump properly.

The signal incorrect faults are because the heights are wrong, and not adjusting. . . . .i.e. not enough air.

If the front airbag is hissing, fix that leak first.

Grrrrrr said:

How long does it take for decent air? Depends how empty the reservoir tank was. The EAS pump isn't designed for big volumes but small volumes at high pressures. To fill the tank from empty will take 5 to 10 minutes. Topping up between height changes maybe 30 seconds.

Click to expand...

+1^^^^^^

Well.
PW - the front is a surprise per se - fronts look rather good / so much as you can see. But it was the rear that was catching up on levelling. The compressor was just progressively running more - but never was anything out of level and on freeway, speed turns or bumps there was never any lag in balance.
On the odd occasion it would drop to entry / bumpers over night but only took a couple minutes to restore.
Just like the "incorrect signal" well it was on bumpers on all four (160 days) but only reported on three and one of those corners (the FL - which appears to be now leaking - same side as the one wheel that didn't report) would appear and disappear as a fault
And the one wheel that has reported "incorrect"- RR - through out reports the same whether there is a HS or not.
And now no change in fault but the two rear are now up on air.


So will try the "bag jump" again - see how it sequences.
See how the rear held over night and start on the front this time.
Do a soap test on everything I can get to - front L bag is an entirely new issue - I had always monitored such things
Then disconnect the compressor discharge line - see if any air bleeds - and then run and see what the output air is like coming out.
Then go over the compressor in detail and the thermal coupling.

I have "real" 4x4's 5T towing 5.3L+ so that is not a concern for the rover.
Given it will be roadway - suggestions for new bags? There are a pile of options
And I will see about a more "effective" OBD reader? The nano seems to be a favorited

There is something happening differently / unreliably with the EAS "box" remote from the computer / EPC
That "corrects" by degree when communication is restored.

Thx - Cheers

Do progressive notes - so I don't forget

all bags dropped what they gained over night
Continuity checked "over heat" sensor - continuity and no resistance at even lowest setting
Relay jumped compressor - checked pressure switch - continuity / closed + 140 psi - 7 min run like yesterday

I swear this machine is messing with me - like an amazonian scandinavian GF in HS

So did PW's C141 jumper process.
Started on fronts this time had (soaped everything - looking for leaks)
Thing shot up to 9" fender over rubber high limit- not a single leak or hiss
Switched to rears again went up nicely a little slower than front - pressure dropping - up to high limit 9" above rubber
All four corners level.
Removed power from jumpers
reconnected C152 - 141
A "minute" later I hear a solenoid or something working for a minute on valve block

Ran RSW a couple times - full process / complete close - restart
First time the three faults - clear faults
Last time only one RR fault Ok HS is not there yet - that makes sense.
Still EAS fault and flashing lights only

Start vehicle up - batteries been running for a bit - and see if it generates communication between all systems.
A couple minutes later I notice a vibration - check - compressor has started up on its own - about four minutes running shut off on its own- big blast of air through exhaust.

Going to leave it for an hour and check air bags, any hissing / restart see what happens.
Did everything the same yesterday - just a little quicker today from prior experience.
Though now I'm choked the new RR HS hasn't arrived - I had even checked with the two shops in town - who deal with old rovers and jag's - if they had a spare
Just remembered - leave a door open and tailgate down so delay relay doesn't do anything

Turned out it was left for four hours - didnt change at all from when it was left
Started it up - top two indicator lights for a minute then flashing four and EAS on dash information
Turned it off and normal locked - that is something that has been noticed if its "acting up" it locks straight to "beep" super lock.

So we will see what it does tomorrow
And see if I can get that replacement HS for the rear right expedited

Cheers,

If it stays up overnight with either door open, or delay relay removed, then it's holding air.

With top two lights on, it's showing the suspension needs to drop to correct standard height. If it then goes to four lights, then a fault is happening. In this situation it generally one of two things. Either sensor value not changing or valves not opening, and either of these will log similar faults.

For the ECU to lower the car it needs to open the exhaust & corresponding corners. If this is not happening, the usual suspect is either intermittent Driver Pack, or the connection underneath the valve block between the driver pack & solenoids. The socket contacts become loose over time, so even if the plug feels tight, the electrical contact can be intermittent.

If one bag is going then they probably all are.

If you're Stateside of the pond then Arnott are probably as cheap as Dunlop bags. I had manufacturing faults with Arnott gen 2 bags from Europe but the gen 3 bags from the States are excellent and if you can pick them up at the right price they're worth it, even without the extra articulation. The main issue with gen 3 bags in Europe is the price: it just isn't worth it at RRP.

Guys,
I thought it was at least positive that it hadn't moved at all in the four hours.
Sh... didnt think to remove relay - and the cover panel is still off
Would have been good to test - but it had only occasionally dropped entry / bumper on its own before.
If it drops to normal ( fender about three inches above rubber) I'll take that as a positive?
So if it drops to bumper I will pop it up again and remove relay - to test

Was pleased to see - with engine running - that the compressor started / stopped on its own to restore tank pressure.
And from completely inflating the system it only ran for about 4 minutes
As well as to see it read / sensed the the high state - (so sensers are working at least levels at and above normal) never tried to adjust as it progressed to flashing.

So it should -on its own- "want" to move to normal running height?
Unless it is reading wheel movement?
With the missing height sensor on RR is that enough to maintain the EAS fault / disable system?
It was still reading that fault - the other two had disappeared.

Do we know what it reads wheel movement from?
On some tests it logs wheel movement but the vehicle has not moved or even put into gear?

As it was rarely on bumpers before and then reporting three not four faults on bumpers originally is it possible that the sensors are "failing" from being on bumpers?
Was temped to run it around the block to see what happened but had run out of time and two vehicles were parked behind it in the driveway.
well maybe try it

Bags, interesting - I thought I read there was an issue with the dunlops at a prior time - offshore manufacturing - I assume that has been corrected?
The pricing is all over the place for both - the Arnott's are generally / depending Gen were more pricey than dunlops.
So Gen / era / where produced were an issue for both of them.
And availability of fronts or rears is the next issue.
Do we think it would matter if you mixed "brands" between front and back pairs?
So current manufactured Dunlops or Arnott Gen 3 are the choice.
It seems there is some "old" stock bouncing around I will have to be cautious of.

Cheers,

frozen north 2 said:

Guys,
I thought it was at least positive that it hadn't moved at all in the four hours.
Sh... didnt think to remove relay - and the cover panel is still off
Would have been good to test - but it had only occasionally dropped entry / bumper on its own before.
If it drops to normal ( fender about three inches above rubber) I'll take that as a positive?
So if it drops to bumper I will pop it up again and remove relay - to test

Was pleased to see - with engine running - that the compressor started / stopped on its own to restore tank pressure.
And from completely inflating the system it only ran for about 4 minutes
As well as to see it read / sensed the the high state - (so sensers are working at least levels at and above normal) never tried to adjust as it progressed to flashing.

So it should -on its own- "want" to move to normal running height?
Unless it is reading wheel movement?
With the missing height sensor on RR is that enough to maintain the EAS fault / disable system?
It was still reading that fault - the other two had disappeared.

Do we know what it reads wheel movement from?
On some tests it logs wheel movement but the vehicle has not moved or even put into gear?

As it was rarely on bumpers before and then reporting three not four faults on bumpers originally is it possible that the sensors are "failing" from being on bumpers?
Was temped to run it around the block to see what happened but had run out of time and two vehicles were parked behind it in the driveway.
well maybe try it

Bags, interesting - I thought I read there was an issue with the dunlops at a prior time - offshore manufacturing - I assume that has been corrected?
The pricing is all over the place for both - the Arnott's are generally / depending Gen were more pricey than dunlops.
So Gen / era / where produced were an issue for both of them.
And availability of fronts or rears is the next issue.
Do we think it would matter if you mixed "brands" between front and back pairs?
So current manufactured Dunlops or Arnott Gen 3 are the choice.
It seems there is some "old" stock bouncing around I will have to be cautious of.

Cheers,

Click to expand...

It would not be a good idea to mix Gen 3 Arnotts on one axle with Dunlops on the other. Gen 3' have different characteristics to the others.

Data - yes that came to mind - was looking for a second
just would like to do all at once - but as it stands maybe doing one axle and then three months later doing the other.
Or waiting a while to do all once. Unless I pay premium and pull from all over the world.
Would just like to get past all of this
Britain has stock / choices but postage and duty is bizarre. Just painfull to buy four and pay for six in some situations.
Couldn't find them on Amazon

Guys,
So, the vehicle held at high level over night dead level on all four -25 hrs
Ran RSW still only one RR - broken HS - Checked "values" on RSW 139 all four corners
Now temped to pull the tire and see if I can J Rig broken HS it to stay in position with only one bolt just to see what happens.
Still flashing changing to solid lights
Pulled out other vehicles and took Rover for a drive around block - at some speed to shake things up -
about 400 ft and heard some four shots of air - and vehicle coming down.
No change to lights etc.
Pull back into driveway and it is sitting at highway driving height.
Before I turned it off I hear the compressor run - stop and then 4 shots of air -
So brining up tank pressure but then balancing out the four corners?
Pulled the delay relay ?? though that doesnt seem to make a difference from previous night.
Guess I have to get the broken case RR HS in place and see what happens.
Well there is definitely some life but

Cheers

Whether driving or stationary, with one HS missing or broken, it will always fault !! At least fix that first.

frozen north 2 said:

Guys,
So, the vehicle held at high level over night dead level on all four -25 hrs
Ran RSW still only one RR - broken HS - Checked "values" on RSW 139 all four corners
Now temped to pull the tire and see if I can J Rig broken HS it to stay in position with only one bolt just to see what happens.
Still flashing changing to solid lights
Pulled out other vehicles and took Rover for a drive around block - at some speed to shake things up -
about 400 ft and heard some four shots of air - and vehicle coming down.
No change to lights etc.
Pull back into driveway and it is sitting at highway driving height.
Before I turned it off I hear the compressor run - stop and then 4 shots of air -
So brining up tank pressure but then balancing out the four corners?
Pulled the delay relay ?? though that doesnt seem to make a difference from previous night.
Guess I have to get the broken case RR HS in place and see what happens.
Well there is definitely some life but

Cheers

Click to expand...

139 on all 4 corners? Calibration needed in that case. You will make no progress until you replace the broken height sensor.

Broken height sensor. Trace wire and see where broken. Of course, it might actually be the sensor.