Do they make a rebuild kit for these compressors and second question is , I know the FE3/F45 Suspension parts are like finding gold on the streets but what about the rear shocks are they as obsolete as the front ? I would like to restore the nice Cadillac ride that this car is known for if at all possible, if it takes me a year to save for the shocks and struts then so be it. I considered the Monroe complete quick strut that has strut/coil assembly all in one, I am getting off subject. I will ask about the front later.
So if the rears are not available either what is a good replacement that will ride well and still have descent handling characteristics?

 

The ELC (Electronic Level Control) compressor runs constantly when there's either an air leak (and the rear of the car does not lift past droop/normal level) or one of the rear height sensors is faulty or its link rod is disconnected.

If the rest of the system is as dirty as the compressor assembly then I suspect either air lines or shock bladders.

If you can't find a new compressor/dryer assembly then Suncore sells reman units. I don't believe there's a rebuild kit out there. ?? RockAuto ?? or maybe www.gmpartsgiant.com.

You might find new F45 CVRSS shocks in gmpartsgiant, otherwise it's the correct Monroe passive shocks with ELC bladders from RockAuto and bypass resistors on the shock wiring pigtail connectors. 1/2 watt 4700 Ohm metal oxide or carbon types, about $1.75 for packs of 5 at www.partsexpress.com.

Google "cadillac forums seville rear level control compressor" or something along that line.

 

The ELC (Electronic Level Control) compressor runs constantly when there's either an air leak (and the rear of the car does not lift past droop/normal level) or one of the rear height sensors is faulty or its link rod is disconnected.

If the rest of the system is as dirty as the compressor assembly then I suspect either air lines or shock bladders.

If you can't find a new compressor/dryer assembly then Suncore sells reman units. I don't believe there's a rebuild kit out there. ?? RockAuto ?? or maybe www.gmpartsgiant.com.

You might find new F45 CVRSS shocks in gmpartsgiant, otherwise it's the correct Monroe passive shocks with ELC bladders from RockAuto and bypass resistors on the shock wiring pigtail connectors. 1/2 watt 4700 Ohm metal oxide or carbon types, about $1.75 for packs of 5 at www.partsexpress.com.

Google "cadillac forums seville rear level control compressor" or something along that line.

View attachment 606965 View attachment 606966 View attachment 606967

 

The exploded view, is that a GMpartsgiant image? Here is everything all cleaning up, it is not all rusted out like a lot of used or rebuilt ones I see on eBay. Wish I could find parts for it, the foam filter on the end of the green line i assume is air being pumped in hose, the foam filter is rotted, and so is the rubber line, it is so old the black from the rubber hoses are rubbing off on me from washing them.

 

Those images are from the online GM/Cadillac/Helm service manuals in www.alldatadiy.com.

The foam is replaceable - it's an air filter for the intake/vent #8.

 

the biggest problem with the compressors is a failed exhaust solenoid -
the compressor constantly runs but never builds up any pressure -
and NO - there isn't a rebuilding kit -

there are a few manufacturers of these compressors -
I recommend the Dorman 949-010 - brand new -
$195 - with free shipping -

Air Compressor, Active Suspension Dorman# 949-010 Fits 98-05 Cad. Deville FWD 37495402125 | eBay

Find many great new & used options and get the best deals for Air Compressor, Active Suspension Dorman# 949-010 Fits 98-05 Cad. Deville FWD at the best online prices at eBay! Free shipping for many products!

www.ebay.com

 

the biggest problem with the compressors is a failed exhaust solenoid -
the compressor constantly runs but never builds up any pressure -
and NO - there isn't a rebuilding kit -

there are a few manufacturers of these compressors -
I recommend the Dorman 949-010 - brand new -
$195 - with free shipping -

Air Compressor, Active Suspension Dorman# 949-010 Fits 98-05 Cad. Deville FWD 37495402125 | eBay

Find many great new & used options and get the best deals for Air Compressor, Active Suspension Dorman# 949-010 Fits 98-05 Cad. Deville FWD at the best online prices at eBay! Free shipping for many products!

www.ebay.com

Good afternoon. I have a question about the rear suspension compressor. I noticed all the new ones I have looked at do not seem to have the air line that has the plastic fitting with foam filter in the end on them. The foam on mine was deteriorated and the rubber hose itself was nearly all dry rotted. I can not seem to find that part by itself anywhere ( the hose with foam filter in end) only compressors I can find that have that included are some off brands I have never heard of on eBay. Any thoughts ? Is the foam an intake hose air filter or something and how important is it? The Dorman 949-010 does not have the line with filter either. Here is an example of a cheap one with the mentioned line with filter. For Cadillac Eldorado Deville Seville 1993-2002 Air Suspension Compressor Pump | eBay

 

Update on the rear air shocks air compressor. I got the Dorman air compressor Bass recommended, installed it and the new Monroe air shocks he recommended. I still have a constant running compressor, I have the rear of the car jacked up with both tires off and I disconnected the rear height sensor rod from both sides so I could manually toggle the sensor up and down to see if the air compressor would shut off, it did not, so what is left for possibilities? Do the 4.7k ohm resistors need to be plugged in before this function works, I know they have to be plugged in to trick the computer since I removed the active suspension shocks and installed the regular Monroe air shocks, just have not done it yet, but did not think it would matter as far as compressor kicking off or on. Could have a leaking air line but that should not matter since I am manually toggling the height sensors up and down by hand. Any thoughts anyone? Only conclusion I have is that both right and left rear height sensors are bad. Not sure why they would be bad, not much to them really.

 

========================
I can't imagine the 4.7K ohm resistors have anything to do with the compressor running -
HOWEVER - I would install them just to eliminate any possibility -

not sure which rear sensor controls ride height -
check BOTH rear sensors -

if you push the arm UP on the sensor -
this would simulate a LOW rear end and should signal the compressor to run -

positioning the arm in the center of travel would simulate LEVEL and should turn the compressor off -

pulling the arm DOWN would simulate a HIGH rear end and should open the EXHAUST solenoid -

if you don't get these results I would check for DTC's -
if no codes - check the ELC compressor relay - under the back seat -
I would swap that relay with another one - just be be sure -

another weird possibility is that the modules "memory" is messed up -
disconnect BOTH battery cables and touch them together for 10 seconds -
this acts like a "reboot"

 

========================
I can't imagine the 4.7K ohm resistors have anything to do with the compressor running -
HOWEVER - I would install them just to eliminate any possibility -

not sure which rear sensor controls ride height -
check BOTH rear sensors -

if you push the arm UP on the sensor -
this would simulate a LOW rear end and should signal the compressor to run -

positioning the arm in the center of travel would simulate LEVEL and should turn the compressor off -

pulling the arm DOWN would simulate a HIGH rear end and should open the EXHAUST solenoid -

if you don't get these results I would check for DTC's -
if no codes - check the ELC compressor relay - under the back seat -
I would swap that relay with another one - just be be sure -

another weird possibility is that the modules "memory" is messed up -
disconnect BOTH battery cables and touch them together for 10 seconds -
this acts like a "reboot"

Will do Bass, thanks a lot.

 

Will these resistors work or do the 4.7 ohm ones have to be used, can not seem to find them at the moment.
I have some that are 5.1k Ohm 1/4 Watt 5% .

 

=====================
I KNOW these will work

$2.69 for a 10-pack - with free shipping -

10 PCS 1/2 w(0.5 watt) 1% metal film resistors Over 200 Various Value YOU CHOOSE | eBay

High Precision Resistors. Quantity: 10 Pieces. Tolerance: 1%. Power (watts): 0.5W (1/2W).

www.ebay.com

 

I think the resistance has to be exact, but dont quote me

 

The front shocks are about ride quality not ELC for rear shocks so adding the resistors does nothing

Not exactly the same, but I had ELC issues with my 1993 Deville 60 special
I replaced the rear ELC type rear shocks but due to the very high price for the fronts and replaced
them with basic front shocks and simply left the wiring connectors floating free and that was 3 years
ago and not even an error code and ELC functions just fine

So with new pump and new rear shocks then if it is not hoses then that leaves
But before going further did you use some soapy water in a spray bottle and from pump back to shocks, with pump running is look for even small leaks in hoses or connectors for them

If no leaks, then put your efforts into :

Check fuses for pump and relay, assure the exhaust solenoid is not stuck open
Check wiring for all three
Check height sensors and wiring for them
Try pulling fuse for relay and see if pump is still active

From my 1993 but related if looking at service manual for your year/model

 

The front shocks are about ride quality not ELC for rear shocks so adding the resistors does nothing

Not exactly the same, but I had ELC issues with my 1993 Deville 60 special
I replaced the rear ELC type rear shocks but due to the very high price for the fronts and replaced
them with basic front shocks and simply left the wiring connectors floating free and that was 3 years
ago and not even an error code and ELC functions just fine

So with new pump and new rear shocks then if it is not hoses then that leaves
But before going further did you use some soapy water in a spray bottle and from pump back to shocks, with pump running is look for even small leaks in hoses or connectors for them

If no leaks, then put your efforts into :

Check fuses for pump and relay, assure the exhaust solenoid is not stuck open
Check wiring for all three
Check height sensors and wiring for them
Try pulling fuse for relay and see if pump is still active

From my 1993 but related if looking at service manual for your year/model

View attachment 615621
View attachment 615620

Thanks for all the input. I was referring to putting the resistors on the rear plugs that were left not plugged in after removing the original electronic shocks from the rear, I installed regular Monroe air shocks in their place. Since the front needs a resistor plugged in the plug I assumed the same would apply to the rear.

 

Is the ride harsh? Does it bottom out in the rear? Have you checked for codes? I have been playing with my '98 SLS recently, and I have a shop manual. If you list the DTCs, I can give you the diagnostic procedure for the DTC.
Here is the shop manual diagram for F45 suspension.
As indicated earlier, if the Exhaust vent in the Compressor Head (Vent in the lower right ALCC module) is stuck open, then the pump will continue to run. In the same fashion, if there is a leak anywhere in the high pressure side, the pump will continue to run.
From the diagram, the control for the compressor is provided by the CVRSS module on the left side of the schematic. It does this by closing the "Compressor Control" solenoid (pin C15 in connector C1 behind the rear seat on the passenger side). The solenoid does this by closing the circuit with a ground. If there is a short to ground anywhere in circuit 321, then there will be no control for the compressor. It will continue to run regardless of the vehicle height sensor input.
So in Summary:
1. Does the vehicle move up as the compressor runs? No=> Leak. Yes=> go to 2.
2. Possible short in circuit 321. You can pull relay 55 in the fuse/relay box located under the rear seat and measure the resistance from the low side of the control circuit. Note that the OMRON relays are reversible (just discovered that!) so you can't put them in the wrong way. The control pins are diagonally located on the relay as are the power pins. The circuit diagram for the relay is painted on the side of the relay, and the pins are identified on the bottom of the relay. Note that the power side of the relay is energized at all times through fuse 64. You can identify this pin by measuring the voltage of each of the connections below the relay with the ignition switch turned off. The diagonally opposite pin will be the low side of the power, or pinout C11 in the schematic. Once you have identified the two pins for the power side, the control connections are the remaining 2. If you now turn the ignition on, you can identify the high side of the control coming from fuse 32. The diagonally opposite pin will be C10 connected by way of circuit 321 to C15/C1 and the Compressor Control output from CVRSS. If you measure the resistance to ground for this pin, it should be very large, > 10 Megaohm. If not, then you have a short to ground in ciruit 321, or the CVRSS module terminal C15 is shorted to ground.
I hope this helps.

 

Is the ride harsh? Does it bottom out in the rear? Have you checked for codes? I have been playing with my '98 SLS recently, and I have a shop manual. If you list the DTCs, I can give you the diagnostic procedure for the DTC.
Here is the shop manual diagram for F45 suspension.
As indicated earlier, if the Exhaust vent in the Compressor Head (Vent in the lower right ALCC module) is stuck open, then the pump will continue to run. In the same fashion, if there is a leak anywhere in the high pressure side, the pump will continue to run.
From the diagram, the control for the compressor is provided by the CVRSS module on the left side of the schematic. It does this by closing the "Compressor Control" solenoid (pin C15 in connector C1 behind the rear seat on the passenger side). The solenoid does this by closing the circuit with a ground. If there is a short to ground anywhere in circuit 321, then there will be no control for the compressor. It will continue to run regardless of the vehicle height sensor input.
So in Summary:
1. Does the vehicle move up as the compressor runs? No=> Leak. Yes=> go to 2.
2. Possible short in circuit 321. You can pull relay 55 in the fuse/relay box located under the rear seat and measure the resistance from the low side of the control circuit. Note that the OMRON relays are reversible (just discovered that!) so you can't put them in the wrong way. The control pins are diagonally located on the relay as are the power pins. The circuit diagram for the relay is painted on the side of the relay, and the pins are identified on the bottom of the relay. Note that the power side of the relay is energized at all times through fuse 64. You can identify this pin by measuring the voltage of each of the connections below the relay with the ignition switch turned off. The diagonally opposite pin will be the low side of the power, or pinout C11 in the schematic. Once you have identified the two pins for the power side, the control connections are the remaining 2. If you now turn the ignition on, you can identify the high side of the control coming from fuse 32. The diagonally opposite pin will be C10 connected by way of circuit 321 to C15/C1 and the Compressor Control output from CVRSS. If you measure the resistance to ground for this pin, it should be very large, > 10 Megaohm. If not, then you have a short to ground in ciruit 321, or the CVRSS module terminal C15 is shorted to ground.
I hope this helps.

This car has been being restored the past 4 years so I can not comment as to how it rides, the original compressor ran constantly when I first bought the car, upon inspection of the original compressor we found a lot of metal shaving inside, it was worn out bad due to it obviously had been running constantly for quite some time. So I bought the Dorman one Bass recommended and the Monroe rear air shocks and installed everything. I will check once the car has the rear tires back on and off of jack stands to see if the shocks air up.

 

The Dorman compressor is brand new so there should be no issues with it.

 

I assume the height sensors being bad is not an option since know one has commented on that or mentions that, it was one of my first thoughts but I do not know a lot about how this ELC ride system works.

 

Ok...but be advised that the new compressor may run constantly also if the control line referenced above is shorted to ground. The compressor on/off switch is located in the CMRSS module behind the rear seat. It does this by connecting the control line from relay 55 in the fuse box located near the battery below the rear seat to ground. If the line shorts to ground somewhere between the fuse box and the CVRSS module, then it makes the control signal from the CVRSS module redundant. The pump will run all of the time until the line is repaired.
If, on the other hand, the old compressor was running because of a leak in the high pressure line feeding the air shocks, then replacing the compressor and NOT fixing the leak will have the same result.
Good luck! If the compressor runs...and raises the rear then you probably do not have a leak. If it teminates after reaching the limit determined by the sensor, all is good!

 

Ok...but be advised that the new compressor may run constantly also if the control line referenced above is shorted to ground. The compressor on/off switch is located in the CMRSS module behind the rear seat. It does this by connecting the control line from relay 55 in the fuse box located near the battery below the rear seat to ground. If the line shorts to ground somewhere between the fuse box and the CVRSS module, then it makes the control signal from the CVRSS module redundant. The pump will run all of the time until the line is repaired.
If, on the other hand, the old compressor was running because of a leak in the high pressure line feeding the air shocks, then replacing the compressor and NOT fixing the leak will have the same result.
Good luck! If the compressor runs...and raises the rear then you probably do not have a leak. If it terminates after reaching the limit determined by the sensor, all is good!

I will update when I find out, but when I removed the rear tires and manually raised up the height control sensor rod it should have shut off the compressor when it was in the proper position, I tried both rear height sensors manually to see if they were working and the compressor would shut off, but if there is a short like you say then even if they were working it would not matter i suppose. Thanks

 

Thanks Bass!

 

What is relay #48 in rear seat fuse box labeled Damper for, anyone know? The relay in that spot is the one that clicks on and off quite a bit like it's opening and closing all the time.

 

==================
DAMPER is another word for strut or shock -
it explains what they actually do -
they DAMPER the reaction of the coil spring -

your STS originally had the electronic F45 DAMPERS -
so - that relay controls the electrical circuit for the DAMPERS -

NO - you can't just remove that relay - it WILL set a number of codes -

it is PART of the reason you had to install the 4.7K ohm resistors - one for each DAMPER -

 

I finally was able to get the rear tires back on and start the car. The rear shocks are airing up and the rear of the car goes up as it should but then I can hear the exhaust valve come on and the shocks release air and the rear end height level goes back down, so the compressor is continuously running, it airs the shocks up then deflates and keeps doing this until I pull the 30 amp ELC fuse in rear seat fuse box.

 

Level sensor may he faulty then I'd say as should not exhaust anything unless something removed from trunk. Not knowing the history of the car was the sensor replaced and possibly wrong one used? Just spit balling.

 

The sensors look to be original ones, 22175743 (LH side) and 22175744 (RH) side.

 

Way back, early in this thread - something is wrong with either the compressor solenoid control head (supply and exhaust) or there's a height sensor problem.

 

The compressor was replaced with a brand new one that Bass suggested, I noted this earlier in the thread. I installed the Dorman unit.

 

Height sensor(s), link rods, electrical connections, and wiring.

 

Yep, I am going to try and trace wires today Sub, the height sensors with the links are attached as they should be, so I guess that leaves electrical issues, there was mention of a possible short to ground in circuit 321 I believe, so I have to figure out where that is and try and follow it. Thanks Sub.