92 eldorado Service Ride Control

[Listerine]

First I just want to say that I'm so thankful to be able to finally join this forum. I've lurked about a while, and now I can finally ask the questions I need to instead of intensly searching threads hoping somebody had my same problems.

But anyway, I guess I'll start off with a seemingly generic topic of the service ride control message. Its a 92 Eldorado, and the only relevant code to this problem I get is IO39. "Loss of road sensing suspension data", sounds pretty vague to me.

Through lots of googling and many times being led to this forum I've found countless possibilities, ranging from the struts to the sensors to whatever else there is. But one thing I thought was pretty interesting that I found here from many years ago was this:


"Code I039 will set if the ignition is on and the IPC is not able to exchange data with the RSS module (if any other communication codes are stored along with I039, see the chart of "MULTIPLE INTERMITTENT CODES"). When this is the only communication code stored, the problem must be one of the following:

An open in CKT 800 between the Electronic Brake and Traction Control Module (EBTCM) and RSS module and an open in CKT 800 between the RSS module and programmer (ACP).
An open or short in the RSS module power or ground circuits.
A faulty RSS module.During the time the failure is present, no RSS diagnostic information will be available for display. The "SERVICE RIDE CONTROL" message will be displayed on the IPC. Also, while in the service diagnostic mode, this code will remain active, always checking for proper operations.


^^^^ If this is correct could someone elaborate a bit? I have no idea what a 'CKT 800' is suppposed to be. But they were talking about a 94 in that thread and I don't know how different those systems are aside from traction control.

But does anybody have idea what that code really means?

The rear auto leveling in my car works as it should. I cant think of what other info you folks may need, but I'll be watching this thread closely.

Keep in mind that I do have a '93 parts car that I can pillage aside from the blown rear shocks.

Thanks!

[Listerine]

does anybody have any input at all? I could really use some direction..

[cctgene]

The trouble shooting flow chart from the 92 FSM for code I039 ask the following questions:

• Is code E024 stored in the diagnostics? (VSS problem)
• Does the speedometer work?

If you have a yes answer then it refers you to the troubleshooting section for that item, if no than it refers you to the system diagnosis for the CCR system. CCR stands for computer command control ride. Since you didn’t mention anything about your speedometer or code E024 I assume your problem is with your CCR, however you know what happens when you assume! Trouble shooting the CCR is a little involved so let me know for sure that the VSS and speedometer can be eliminated as the source of your problems.

[Listerine]

Hi cctgene,

Code EO24 is not present and my speedometer works, so I guess your assumption is correct.

Thank you going out of your way to look it up in the service manual..I really need to get my hands on one. If you would describe the procedure to me I would greatly appreciate it, I can't seem to find anything about the procedure on the internet.

[2001_Seville_SLS]

If this is correct could someone elaborate a bit? I have no idea what a 'CKT 800' is suppposed to be. But they were talking about a 94 in that thread and I don't know how different those systems are aside from traction control.

But does anybody have idea what that code really means?

The rear auto leveling in my car works as it should.

Yes. The information you found is correct. The code means that the road sensing suspension module (RSS) is not operating correctly. The auto level is a separate system, but shares non communication circuits with the RSS. The spare parts car might be handy if you need the module, but what you really need is a multimeter. If you don't have one yet - get one.

The first thing to check is the B+ power to the RSS module. There is more than one supply. Check the fuses in the rear block. I only have the 00-03 diagrams. On the 01 they are called CVRTD and IGN 3 RR. I am not sure about the 92 so just check them all. If the fuse is bad, look for an intermittant short to ground.

If the fuses are good then unclip the connector at the RSS module and check all of the power supplies at the harness side of the RSS module connector with the ignition ON but not running. On the '01 it is behind the left rear seat and accessed thru the trunk. You will need a wiring diagram from the service manual to locate the proper pins. They probably have it in the library, or maybe someone will post the '92 RSS wiring diagram for you. You could find them without a diagram by observing the meter when you pull the fuses, but it is worlds easier with the diagram.

If the power supply is good check the ground(s) at the RSS connector with an ohm meter against a good ground.

If both the power supply and the ground(s) are good, then check circuit 800. You are in luck, because someone recently posted the communication circuit diagram for a '95 which goes with the trouble code description for the '94 that you provided. I am not sure if the '92 is the same, so check the wiring diagram and adjust accordingly if necessary.

To check circuit 800 for the RSS per the '95 diagram, unclip the connectors to the EBTCM and the heater and AC programer, then using the ohm meter at heater C10 (tan) and EBTCM 29 (tan). You are looking for close to zero ohms. If it is not good, then check from the AC to RSS and RSS to EBTCM to locate the problem.

You didn't mention if the code is always current, sometimes current, or history. If it is sometimes current or history then, on all of the tests you will also need to lightly tap the harness at various locations while observing the needle to find intermittent problems.

Good luck. I hope it is just a fuse.

[cctgene]

The section in the 92 FSM that covers the CCR consists of 20 pages and this does not include the three pages of the related wiring diagrams. Obviously this is more territory than I can practically cover here but what you can do for starters is to pull and clear the codes and who knows maybe you’ll get lucky!

The process to pull the CCR codes is different than the other available diagnostics codes. The following is verbatim from FSM:

The CCR system has a control module, which is located in the right electronics bay in the trunk. This module stores error codes and they can be viewed via a light emitting diode on the module itself. There are a total of 7 possible codes they are as follows:

• Code 12 Initiation Code
• Code 23 Left FRONT Actuator Error
• Code 24 Right Front Actuator Error
• Code 25 Left Rear Actuator Error
• Code 26 Right Rear Actuator Error
• Code 31 Lift/Drive Input Error
• Code 32 Lateral Acceleration Switch Error

The CCR diagnostic systems may be actuated by grounding the diagnostic enable circuit at pin C of the ALDL connector or by grounding pin D2 to D16, of the control module connector. After pin C is grounded the lamp will be on for 7.5 seconds before beginning the blink code diagnostic sequence. This followed by displaying code 12, three times to mark the beginning of the sequence. Then each stored code is blinked out, in ascending order. Each code is displayed three times before proceeding to the next code when all codes have been read, the entire code sequence will repeat, starting by blinking code three times. The sequence will repeat until the diagnostic enable circuit is disconnected.

Codes are read by counting the number of flashes of the L.E. D. on the CCR control module. A code 12 would be indicated by the lamp flashing once, followed by a one second pause, followed by two flashes with a half second pause between flashes. There is a three second pause between codes.

If the diagnostic mode is entered, and no codes are stored in memory, the control module will continually display code 12.

The error codes can be cleared by grounding the diagnostic enable circuit (pin C to pin A of the ALDL connector) or pin D2 to D16 of the control module connector) three times (for approximately one second duration each) within 30 seconds. The control module indicates codes clear by turning the error lamp off for one second. The codes are not cleared when the battery or control module connectors are disconnected.

End of verbatim.

In case you don’t know where the ALDL connector is, it’s located to the left of the steering column under the hood release.

If you’re able to pull any of the codes and clearing the codes doesn’t make it go away post the code or codes and well go from there.

[2001_Seville_SLS]

I did a search to see if the '94 and '95 info applies to your '92 and it looks like it does not. My info will only help you if you have a '94 era car with a RSS that is not communicating and it looks like you don't... Oops.

I think you should follow cctgene's advice. There is a Deville post that indicates the Seville system changed after '93 and provides a method to disable the system if OEM parts are not available. Here it is in full:

That thread has 151 posts. Here's what I've extracted of interest to me. I should be giving credit to the posters of these gems. Thanks guys.

You get into the SSS/CCR system by grounding pin 'C' on the ALDL. On the module there is a white plastic window with a LED behind it. It will flash codes after pin 'C' is grounded. It will repeat the codes as long as it is grounded. Kind of like the older GM flash diagnostics.

Code-
12 diagnostic mode
23 left front strut
24 right front strut
25 left rear strut
26 right rear strut
31 lift/dive input error
32 lateral acceleration error
35 speed-sensitive steering error

most of us deville guys have our modules in the trunk , there mounted to the back of the rear seat behind a carpet panel witht he suspesnion being almost all the way to the passenger side , we take the panel out to gain acess to the modules (theres a pass key and a couple other modules in adittion to the suspseion module) our suspension modules are held in by two 7mm screws , window can be seen clearly once the module is unbolted.

Info -- Procedure to Disable Illumination of Service Indicator AFTER installing Passive Struts #00-03-11-001A

Applies to:
 1989-1992 Cadillac Allante
 1991-1993 Cadillac Eldorado, Seville
 1991-1995 Cadillac DeVille
This bulletin is being revised to clarify when this bulletin may be used to turn the service suspension lamp off. Also, a step has been added to the 1991 Cadillac Eldorado and Seville repair. Please discard Corporate Bulletin Number 00-03-11-001 (Section 3 -- Suspension)
Some owners may bring their vehicles in for service with an illuminated service suspension light. The service suspension indicator lamp is telling the owner that the vehicle is due for strut/shock replacement, a maintenance item. The customer may elect to have passive struts installed in their vehicles due to the repair cost savings and/or parts availability. The installation of passive shock/struts will result in handling characteristics which are the equal to a like vehicle without the computer controlled ride, with all other components such as tires, tire pressure, springs, etc. being equal. The installation of (4) new passive struts will cause the continued illumination of the service suspension indicator. If desired by the customer, the service indicator may be disabled AFTER THE INSTALLATION OF THE (4) NEW PASSIVE STRUTS, using the appropriate service procedure listed below. This bulletin DOES NOT authorize this procedure unless (4) NEW PASSIVE STRUTS WERE INSTALLED ON THE VEHICLE.
The wiring harness going to each strut and or chock assembly should be cut and taped back to clean-up the appearance both under the hood and under the vehicle. In addition, each specific vehicle will require a modification as outlined below:
 1989-1992 Allante with Speed Dependent Damping (SDD): Refer to the Service Manual page 8D-13 (1989) or 8D-14 (1990-1992). On these vehicles, adjust the BCM Override value "BS08". To do this, use the warmer/cooler button on the CCDIC to decrease the BCM override value "BS08" which is displayed when you enter the system by two(2). When the desired number is displayed on the CCDIC, it must be stored by holding the "Elapsed Time" and "Fuel Used" buttons until the new value flashes on and off. When it flashes on and off, the new value has been stored.
 1991 Eldorado and Seville with Computer Command Ride (CCR): Refer to the Service Manual page 8D-12. Set the BCM override value BS09 to 0 by using the warmer and cooler buttons. Store this value by pressing the Econ button on the climate control panel and the Instant Econ button on the Fuel Data/Drivers Information Center for about five seconds. The new value will be stored even through the indicator does not flash. Remove the key from the ignition. Disconnect both battery cables from the battery. When both cables have been disconnected, touch the ends of the cables together and hold for five seconds. This will discharge the capacitors in the system and allow the system to perform properly when the battery cables are reconnected. Advise the customer they will have to reset all radio stations and clock.
 1993 Eldorado and Seville with Speed Sensitive Suspension and 4.9L Engine Only: Refer to page 8A-43-6 in the 1992 Eldorado Seville Service Manual.
 Cut Circuit 1020 (PINK)
 Attach the IPC side of circuit 1020 to relay pin 87A
 Attach the module side of circuit 1020 to relay pin 86
 Run a ground wire to relay pin 30
 Run a wire from a switched ignition (hot in run) source to relay pin 85.
 1991-1993 DeVille with Computer Command Ride (CCR): Refer to the Service Manual, page 8A-43-0. Cut Circuit 1300 (Dark Green wire) at the CCR module (Pin C15) to disable the indicator lamp. Tape the wires back into the harness to prevent shorting to other components.
 1994-1995 DeVille with Speed Sensitive Suspension (SSS) and 4.9L Engines ONLY: Refer to the 1994 Eldorado, Seville, DeVille Service Manual, page 8A-43-14:
 Locate and cut circuit 370 (RED)
 Attach the IPC side of circuit 370 to pin 87A of the relay
 Attach the module side of circuit 370 to pin 86 of the relay
 Run a ground wire to relay pin 30
 Run a wire from a switched ignition (hot in run) source to relay pin 85.
 The following part numbers are required to make the correction on the 1993 Eldorado/Seville and the 1994-1995 DeVille:

Part Number
Description
Qty
12193601
Relay
1
15306045
Connector
1

Parts are currently available from GMSPO.


FYI the above procedure worked like a charm on our 94 Deville with 4.9. There is no need to get the GM parts listed above. I got a $4 generic relay at the parts store and it worked great. It is very easy to do this install. It took me about 15 minutes. Here are more details in case anyone is interested:

Parts needed: generic relay (most have the same numbers as in the above directions: 85,86,87a, 30) . The relays are on the shelf near the fuses at most parts stores. Some quarter inch female terminals, a couple of feet of 16 or 18 gauge wire, two splice doohickeys for tapping into wires without having to cut them. A couple of small wire nuts.

1. Locate the module in the right rear compartment of trunk.
2. Locate three wires: Red (circuit 370) I think this is C15 on the plug, Brwn 12 V ( C16)this is near the red wire and black ground (D15) is also near the red wire. The shop manual 800-43-14 shows the diagram with the correct labels.
3. Wire the relay as described above. you only need to cut one wire, the red one. The black and brown can be tapped without cutting.
4. After wiring is done you can attach the relay to the board with a small screw, there are several locations for doing this.

That is it. All this does is force a polarity reverse for the red IPC circuit. When the module tries to ground the red wire to send the SRC message, this relay is energized and forces an open circuit. I wish we had done this 3 years ago. It is so nice to not see that annoying message, no more having to push the information button!

Well, here's my $.02. I happen to work at a Cadillac Dealer doing steering n suspension. The code doesnt really mean much. You are suppose to ground terminal c to ground and count the # of flashes on your ride control module in the trunk. Very simple. But anyways. You cant get OEM parts forthis car anymore. But you can get a Bypass kit. YOu wire it in the trunk inline w/ your ride control module and the light will never come on again. As long as your car doesnt ride bad its probably just the electronic part of a strut that has went bad. Someone may have already said this but there were to many replies to your question to read them all.

[Listerine]

Well I tried the CCR diagnostic procedure to no avail. I'm not sure what I was doing wrong, I simply grounded one end of the wire to the door hinge and tried all of the pinholes in the ALDL (since I wasn't sure which one pin c was) in the plug with no light up in the trunk. Unless my friend didn't see the light, somethings wrong. I'm pretty sure it was a clean ground.

I will admit the module is kind of hard for me to identify since there are a few on the right, but descriptions Ive found point to the large silver one. I think I've also found a green light on it. A red light comes on for a couple second then shuts off on a smaller black module below the silver one when I turn the key on..I'm not sure if that's what I'm supposed to be looking at or not.

Could you possibly tell me which plug the control module connector is so that I may try that way? There are a few plugs with many tiny pins.

I feel pretty silly right now, sounds like such a simple procedure and I cant pull it off. But I shall keep trying.

[cctgene]

See if this helps.

[Listerine]

Thank you for taking those pictures they did indeed help. I didn't realize I had to have it grounded before the key was turned, and the ground was also pretty crappy.

But anyway the codes flashed were codes 23, 24, and 26. I cleared them and did the procedure again but they were still there.

So will those parts in error simply have to be replaced or is there possibly more to testing them?

[cctgene]

This is the next step. The test for all three codes are the same except for the pins where you take the measurements.

Code 23 between pins D13 AND D11
Code 24 between pins C13 AND D10
Code 26 between pins C14 AND D8

The circuit numbers and the wiring color codes are of course different but I don't think you need them for these test.

[The Gold]

bump up for forum

Listerine, what became of your efforts? any luck??