: 1987 Brougham automatic level control



TopherS
09-25-11, 07:23 PM
I've another question about my new Brougham. It has the electronic level control (according to the original window sticker). When I turn the car on, the light on the dash does not come on, nor does it come on at any time. I was thinking that perhaps a fuse was blown, but I can't find which fuse it is. The owners manual has the fuse chart/locations, but says nothing about the ELC. There is a relay, I believe, but I understand that the relays will trip when overheated and come back on when cooled...so I wasn't thinking it was a relay. The car seems only a little low, but I'd like to know if the system even is working. I don't hear anything like a compressor working.

Which fuse protects the ELC system?

How can I check this system out?

Thanks again for the help.

drmenard
09-25-11, 08:22 PM
There are two fuses in the ELC circut...20A body and GA Trans 20A...and there is a relay in the relay center..The fuse box and relays are under the dash on drivers side.Looking at the fuse box , starting at the bottom, the first row has only one fuse.. the second row up has only one fuse.. the third row up has 3 fuses.. the body fuse is the 20A on the right... The 4th row up has 3 fuses and the GA Trans fuse is the one on the left...Looking at the relay board there are 10 relay spots and there are 8 fuse spots, not all being used ...now if your looking at the relay board and the fuses are on the right and relays on left.. the relay is on the top row second relay in .. thats going from left to right..so now you should be able to check those things...I got this info out of a 85 book... I hope its the same...

sven914
09-25-11, 10:32 PM
The bulb could be burned out, so don't go by that...

Next time you go out to your car, open the hood and leave the door open. Turn the ignition to RUN, but don't start the engine. After about 30 second, you should hear the ELC pump turn on.

If you do not hear it engage, check to see if the compressor is plugged in. It is located on the driver's side fender well, near the fire wall, and has a 4-pin connector. If it is not plugged in, just be aware that is a reason why it was disconnected.

If the compressor is plugged in, but isn't coming on, check the body fuse, the GA trans-fuse, and the relay. If all of those things are good, the height sensor (on the rear suspension) may need to be readjusted or replace.

If, when the compressor is plugged in, it runs continuously (doesn't stop within 7 minutes), then the relay may be stuck or the height sensor could be faulty. You can also check to see if either the dark green wire (on the ELC connector) or the yellow wire (there's a test connector in ELC harness, by the brake booster) are shorted to ground.

TopherS
09-25-11, 11:52 PM
Brilliant.

So I turned the car to RUN and opened the hood. From the ELC components, I heard a click about 20 seconds in and then another click about 10-15 seconds afterward...but nothing otherwise. The 4-wire connector is plugged in. It's too dark, so I'll have to check the fuses tomorrow to see. I'll post back.

Cheers. Thanks a lot.

TopherS
09-27-11, 01:42 AM
Update:

I checked the "Level Ride" bulb and the two 20-A fuses...all good.

I believe I found the correct relay, but don't know how to test it to see if it's good.

The 4-wire connector under the hood was connected.

I turn on the car w/ the hood open...about 20-30 seconds later, I hear a click from the ELC component...about 15-20 seconds later, another click...but no compressor noise otherwise.

Any ideas on where to look next? How can I test the relay...should I just buy a new one?

Thanks!!!

sven914
09-27-11, 11:13 AM
I don't know how much the relays cost, but if you can get one cheap enough, it can't hurt to replace it.

carnut
09-29-11, 03:54 PM
Get under the car and locate the height sensor that attaches to the left rear trailing arm. The rod to the sensor pops off a ball stud. With the key on, engine off, pop off the rod from the trailing arm and push the level ride arm up towards the trunk floor. Within 8 to 13 seconds you should hear the underhood pump turn on and you should see the rubber bags on the 2 shocks begin to swell up. Pull the lever down and the pump should stop. This system only works when the load increases by at least 300 LB in the trunk or rear seat. We used to test the system at the shop by turning the key to run then have two 200 LB people sit on the rear bumper! Within 8 to 13 seconds the pump could be heard turning on and the rear of the car went up slightly.

TopherS
10-08-11, 05:18 PM
So I just popped off the arm from the ball stud and raised it toward the trunk floor (propping the arm up on the trailing arm to give the impression that the back of the car was weighed down). I turned the car to on and stood next to the compressor under the hood...and nothing. I got another click but that was all.

Where should I check next?

carnut
10-08-11, 09:19 PM
With the key turned to the run position, move the shifter from park to reverse then back to park. That resets the timer and after 8 to 13 seconds the pump should turn on. If that doesnt work then locate the green test wire in the loom that goes to the pump and using a jumper wire, run that wire to the positive post on the battery. That should turn on the pump and start to raise the rear of the car. If that works then I would look for an open circuit starting with the fuse.

brougham
10-10-11, 01:29 PM
That clicking noise it makes under the hood sounds like the right timing for when the compressor should be running. So the system should be working properly and tellhing the copressor to come on but either something is wrong with the compressor or it's not getting power to do anything.

sven914
10-10-11, 03:06 PM
The compressor could be dead.

TopherS
10-10-11, 05:06 PM
Yesterday, I replaced the relay...just in case. Same result...a pair of clicks...sounds like it clicks on, then off. Nothing more...

I noticed that the green wire going to the compressor has a staple punched through it...so I'm assuming that the previous owner had attempted to work on this issue. I got out a wire-tester and clipped the clip to the battery-positive post and touched the wire-tester to the staple through the green wire and the tester lit up...although, nothing happened with the compressor (it didn't activate or anything).

I still need to try what Carnut said about attaching a jump wire to the compressor from the battery-positive post (I'm sure the wire-tester wasn't substantial enough to make anything happen).

But, I'm wondering this...assuming the compressor is dead...and the clicks I hear are the system (trying to) turn on the compressor and back off again... should the "Level Ride" light still light up during the time that the compressor should be running? Perhaps a better way to ask it this is...is the "Level Ride" light dependent upon the compressor running or is it independent of the compressor? I ask this because at this time, the "Level Ride" light is not lighting up at all...ever. I've tested the bulb and the bulb is good.

I could look into replacing the compressor to see what happens. I went to one of the junkyards yesterday and they did not have any RWD cars there (except a '76). They had an 80-85 Seville and about 3 '91-93 deVilles. Are there any vehicles with which the compressor on my Brougham interchanges? Are there any sources for compressors out there?

I do appreciate all y'all's help on this.

notease
10-11-11, 02:58 PM
Just to hook up into this thread, Mine Level Ride lights is also not on all the time, should it be ?
And what about the yellow test wire near the Brake valve in the test loom to the ELC ?

sven914
10-11-11, 04:45 PM
^My Level Ride indicator lamp is inoperative, but my level ride compressor and shocks are fully functional. The bulb works, but the printed circuit, around the indicator, is messed up and the bulb will never light.

In a properly working system (with a working bulb) the Level Ride indicator is supposed to come on once per ignition cycle, for about twenty seconds while the compressor runs. If yous does that, your system is functioning as it should.

carnut
10-11-11, 09:55 PM
The system only works when it needs to. The level ride light will only come on when the compressor is runnning. Unless the load in the trunk or back seat has changed, the level ride will not function. Assuming no leaks and 1 driver, the system keep about 20 LB in the shocks.

notease
10-12-11, 05:16 AM
The bulb going on is then when i think the system tells the ELC to start the compressor, but it does not indicatie if its really runnning.
My lamp goes on sometimes but when i bought my Ride the connector at the compressor was disconnected, and still the bulb goes on sometimes if even with loose connector.
When i connect the connector the compressor immiadtly starts to run, how and when is the pump telled to stop pumping ? The control arm on the rear axle with the sensor ?

carnut
10-12-11, 10:29 AM
The height sensor mounted at the rear completes the circuit once the lever moves to the preset trim height and then the pump shuts off. The pump will run for 5 minutes even with a massive air leak and will shut off. I would follow the air lines and look for a broken/ disconnected hose or a torn boot on one of the rear shocks.

TopherS
10-12-11, 01:10 PM
The system only works when it needs to. The level ride light will only come on when the compressor is runnning. Unless the load in the trunk or back seat has changed, the level ride will not function. Assuming no leaks and 1 driver, the system keep about 20 LB in the shocks.

This has got me thinking that perhaps, my system is working somewhat as it should. About 99% of the time, it's just me in the car. If the family gets in the car, then it's me and the wife and our two kids (12 and 9 years old). I've NEVER seen the "Level Ride" light go on, but the car does not appear to be too low in the rear. My car has about 1" whitewalls on it and the rear fender goes through the whitewalls (but above the wheel covers). I don't know if this is how it should be, but sitting on level ground, I put a 3' level along the trim piece that goes along the side of the car (body-colored trim) and it was perfectly level. I never seem to bottom out on anything.

I've never had a Cadillac before. Two of my previous cars, a 2001 Park Avenue and a 1995 Roadmaster, had auto-levelers and you could hear the compressor pumping but neither had a "Level Ride" light to indicate that the system was working. The wife's 2006 Town & Country has auto-levelers, but it uses some sort of shocks that level themselves without a compressor. Cadillac's system is new to me. I was just going by the owner's manual that says the system will go on for a few seconds each time the car is started and I've never seen it do it. I may have to play with this a bit more.

carnut
10-12-11, 07:08 PM
Simply turn the key to run, (do not start the engine) shift it from park to reverse then back to park and you and a friend go sit on the rear bumper on level ground. Within 8 to 13 seconds, the pump should turn on and the car will raise, if working as designed. My 84 Sedan also has an inch whitewall and I readjusted the level ride sensor arm up so now the whole white wall shows.

brougham
10-12-11, 07:56 PM
This has got me thinking that perhaps, my system is working somewhat as it should. About 99% of the time, it's just me in the car. If the family gets in the car, then it's me and the wife and our two kids (12 and 9 years old). I've NEVER seen the "Level Ride" light go on, but the car does not appear to be too low in the rear. My car has about 1" whitewalls on it and the rear fender goes through the whitewalls (but above the wheel covers). I don't know if this is how it should be, but sitting on level ground, I put a 3' level along the trim piece that goes along the side of the car (body-colored trim) and it was perfectly level. I never seem to bottom out on anything.

I've never had a Cadillac before. Two of my previous cars, a 2001 Park Avenue and a 1995 Roadmaster, had auto-levelers and you could hear the compressor pumping but neither had a "Level Ride" light to indicate that the system was working. The wife's 2006 Town & Country has auto-levelers, but it uses some sort of shocks that level themselves without a compressor. Cadillac's system is new to me. I was just going by the owner's manual that says the system will go on for a few seconds each time the car is started and I've never seen it do it. I may have to play with this a bit more.

Well at least that shows the suspension is good and holding the car up properly. The auto leveling isn't made to always hold up the car, only compensate for load. There's still something wrong with it tho since it doesn't come on at start up.

carnut
10-12-11, 11:32 PM
I beg to differ! The level ride system should ALWAYS have a minimum of 20 Lb of air in the rear shocks. Yes it does hold up the rear of the car. The coil spring's load rating is set anticipating air in the rear shocks. Unless you increase the load prior to start up, ( Mother in law, or baggage) there will be no level ride light 95% of the time upon 1st start . The compressor is wired thru the run side of the switch so it can only run with key on. The exhaust side, though, is powered all the time. So after the load's been removed, it can exhaust and return to proper ride height.

sven914
10-13-11, 01:08 AM
^The system maintains a minimum of 7 PSI...

According to the service information in my factory service manual, "The compressor is activated when the ignition is on and excess weight is added to the vehicle." The service manual outlines the system check as turning the ignition ON/OFF/ON to reset the ELC timer (changing gears is not parameter for resting the system) and then adding weight of 300lbs to the trunk. There is no mention of the system being active without additional weight being added.

The system description, outlined in the owners manual, states "In a normal system (one or two passenger load), the LEVEL RIDE will come on approximately 35 seconds after starting and run for 4 seconds." This description coincides perfectly with my experience of how the ELC system operates. It is not contingent on load.

This is a perfect example of the service information not being relevant to a real world scenario. As a technician, I'm sure you know that there is a difference between how something is technically supposed to work and how it actually functions.

brougham
10-13-11, 02:29 AM
I beg to differ! The level ride system should ALWAYS have a minimum of 20 Lb of air in the rear shocks. Yes it does hold up the rear of the car. The coil spring's load rating is set anticipating air in the rear shocks. Unless you increase the load prior to start up, ( Mother in law, or baggage) there will be no level ride light 95% of the time upon 1st start . The compressor is wired thru the run side of the switch so it can only run with key on. The exhaust side, though, is powered all the time. So after the load's been removed, it can exhaust and return to proper ride height.

There is always some pressure in it but with no load it hardly holds the car up at all. That's the springs job to do. The level ride system is only there to compensate for load added to the car. With TopherS's car sitting at the normal height with the system supposedly not working indicates that the rest of his suspension is up to par.

The compressor should come on every time the key is turned on whethere there is additional load in the car or not. If there is additional load in the car before it is started it will just run a bit longer.

carnut
10-13-11, 11:48 AM
Must be different on an 84. The FSM says the system keeps a min. of 20lb in the shocks. It also states without a small amount of air staying in the shocks, ride trim height and ride in general will deteriorate. Because I rarely have anyone in the back seat, the level ride system has no need to adjust the trim height hence no light, no pump activation. Even at 7 lb, it is holding up the rear of the car. This is my 3rd 84, 2 Eldo's and now a Sedan. My first never showed a light nor activated unless the load was changed prior to start up, my second would come on for a few seconds if it wasn't driven for a few days and I attributed that to a small leak somewhere in the system. My sedan only comes on when 3 people are in the car. My manual also states to move the shifter from park to reverse then back to park (key on) to reset the delay timer. Its very easy to verify the shocks are holding air, get under the rear of the car and feel the air boots on the shocks. On an Eldo or Seville you just reach behind the tire to feel the boots. They either have air in them or not. It also states that with the extra load, the pump and light might come on as driven to make slight changes in trim height. I agree, most cars do not depend on a shock to support the car. Level ride equipped cars do. I might mention that on all 3 cars I adjusted the level ride height sensor arm up within a week of ownership to slightly stiffen the rear suspension. That might account for the system rarely needing to activate. This scenario describes the system on 82 thru 85 level ride equipped Cadillacs.

brougham
10-13-11, 11:21 PM
They must have changed the system at some point unless it's the difference in body styles. 88 Deville/Fleetwoods work the same way sven described so if it was a change it must have happened in 86 or 87.

Even with auto leveling the only time the car should be dependent on the shocks to support it is when there is load. At that point it does depend on them more then a normal car to make up for the softer springs.

sven914
10-14-11, 01:04 AM
The system was probably updated when Cadillac came out with the new body styles. It's good to know that the ELC worked differently in '84 (I always assumed all RWDs worked the same).

TopherS
11-06-11, 11:02 PM
So I decided to play with this problem again a little bit today...see what I could see...

I figured I would first try out the test wire (by the way, it's yellow on my 87'). When I jumped it to the battery-positive, I could hear the same clicking coming out of the compressor that I was hearing when I would turn the car on and listen. There was no other activity within the compressor.

Would I be correct in assuming then that my compressor is dead?

We have a junkyard here that is GM-specific. The man working there said they either get requests for compressors or for the height sensors on the rear axle...he wasn't aware of any other parts to the level ride system that were replaceable. I was there for a completely different part and only mentioned that the next project on my car was the level ride system. He has an 87' and (I think) an 84' Cadillac (RWD models) but he didn't know if either had the level ride system and I did not ask him to check at the time. But perhaps this next weekend will be when I start looking to replace parts here. Of course, I will ask about the 87' first...but just in case...

What model years' compressors are interchangeable?

Are there any other GM cars that have compressors that are interchangeable with the 87' Brougham?


Again, thanks for your help.

brougham
11-07-11, 09:52 PM
A lot of the compressors are probably similar. The best way to tell is just compare it to yours.

Robin Banx
11-07-11, 10:34 PM
I figured I would first try out the test wire (by the way, it's yellow on my 87'). When I jumped it to the battery-positive, I could hear the same clicking coming out of the compressor that I was hearing when I would turn the car on and listen. There was no other activity within the compressor.

Would I be correct in assuming then that my compressor is dead?

Don't assume that your compressor is dead without hot wiring it directly to the battery. If it does not run, then you can class it as "dead". The only time I see my Level Ride light on on the dash is when I run the car low on fuel and then fill it up. The Level Ride light comes on until the compressor has restored the height (usually less than one minute).
Cheers...R
Cheers....R.

ChatWithaNinja
11-12-11, 12:49 PM
I've been following this thread because I am also having problems with my auto leveling.
What I need to know to stay on topic is what sounds the air pump makes when it runs.
I did the test with turning on the ignition (but not the engine) and waiting for the pump to come on. My pump comes on for about 5 seconds (scared the crap out of me when it did because my head was right next to it thinking it would be quiet) and then when it turns off, there is an escaping of air for about 2 seconds. Brrrrrrrrrrrrrrrrrrrrrrrrr:Hisssss
Is that right or do I have a bad pump?

I'll put my other questions in a separate thread, I don't want to hijack this topic completely.
Thanks.

425 Dual Quad
11-12-11, 02:04 PM
ChatwithaNinja,
That is the sound your compressor should make. So it sounds like yours is fine.
regards, Nick

TopherS
11-12-11, 06:41 PM
ChatwithaNinja, thanks for your courtesy about thread-hijacking. :thumbsup: I'm actually glad you chimed in, though, because that's a question I was planning to pose to the group. Now I know what to listen for. I've had other cars with ALC and wasn't sure if this car would have a different sound when the compressor is pumping.

I went to a salvage yard and got a compressor from an 86' Fleetwood and put it on the car...same result..."click" is all that I hear...and no "Level Ride" light. I decided to pass on the compressor, as it was acting the same way my current compressor is acting.

So I thought that perhaps, it was the sensor on the rear of the car. Mine, when I pop off the arm from the ball-stud, was very loose and the entire arm would fall straight down. I decided to get the sensor from the 86'. I installed it on the car, and it appears that it is a good sensor. With the arm not attached to the ball-stud, I can move it up or down and it will stay in position. The compressor still won't go on, but I can control the "clicks" by moving the sensor arm up and down.

I'm not sure that the compressor I passed on was good or bad. But... before I go on the hunt for another one...or go back and try that one (with the new sensor now installed), I have another question:

Other than the compressor and the sensor, is there any other component I should be checking out? (btw, I've replaced the relay under the dash)