Autoride Logic Diagram and Data Flow Chart

[Grady_Wilson]

Does anyone have a complete logic diagram or data flow chart for the Autoride suspension?

What I am looking for is how the entire system reacts and processes the input from each of the sensors and data points in the system.
What, exactly does each shock sensor send to the controller and how does the controller process that information?

To me, the only logical way to make an informed decision on whether to replace the Autoride with a standard system, or replace the Autoride shocks with airbag shocks with a dummy sensor, is to know exactly how each pieces operates and provides feedback to the system.

Without this, you would just be guessing at how it will effect the overall ride and system.

I need to replace the rear shocks on my Denali and cost is not the biggest factor for me.
I want to know what I am gaining or losing by choosing each option available for replacement parts.

Thanks.

 

[Doubeleive]

the best choice is to replace the defective parts with oem or a comparible product that will function like oem, for instance arnott makes a replacement oem compatible shock that operates just like oem, they also make one that has a buiilt in resistor that "lies" to the computer and it thinks everything is normal.
the there are basically 9 components of the air ride system
4 shocks
4 ride height sensors
1 pump
and I guess the computer counts as well
without going into technical never never land it basically works like this (i think)
each of the 4 ride height sensors are your data source, these send data to the computer and in return the computer sends data to the shock to soften or harden the fluid resistance inside and to the air pump to increase or lower the rear shock bladder psi pressure. (the air psi lifts or lowers the rear end depending on the load like bags of cement or a trailer attached, etc)
in a nutshell I believe that is how it works
when you use a standard shock with a resistor or "resistor" on the shock it basically accepts the signal from the computer but doesn't change anything because it can't it's just a dummy shock.
the resistor is a specific "ohm" that the computer see's and accept's as "normal" therefore it thinks everything is fine and dandy.

if you just throw any old shock on there with no resistor or if the resistor is not the correct ohm or fails, the computer see's it as a open circuit and can or will throw a error message

 

[petethepug]

Research z55 / z95 / AutoRide / Magneride bypass “still have codes after bypass/resistors added”.

The replacement struts from GM have a lifetime guarantee. They do go on sale during the holidays.

The info your looking for is what Delphi techs pioneered and still selling. It’s proprietary info they hold sacred so they can recapture their R&D and technology in creating their product. Could you figure it out? Sure, eventually, but I sure won’t guess on how long it’d take.

Either…

* Sell the truck with bad shocks and make some good $ to buy a Non z55 vehicle.
* Replace your z55 struts one more time to get lifetime z55 struts.
* Jerryrig hydraulic struts and hobby resistors into the system. Chase DTC, add more codes to pop up in the dash and time wasted.

Good Lord, it has Cadillac’s first Gen z55 air and active suspension guaranteed for life. I’d guess $180-$250 per corner, one more time, bolt on, bolt off in back. Really? The same GM struts were $500 ea 10 years ago. What gives?

 

[Grady_Wilson]

I plan on replacing the rears with some Arnott shocks as they seem to be the closest to the AC Delco shocks but without the sticker shock.

I will keep an eye out for a sale on the front struts this holiday season.
A lifetime warranty sounds good to me. I normally purchase Monroe shocks and struts for my other vehicles because they also have a lifetime warranty. Replacing them costs only my time.

As someone in the IT world, I wanted to know what the exact logic process was and how everything operated.
Not that I was going to make drastic changes to the system, but I want to understand how the system functions.
This not only allows me to make better decisions on replacement parts but also during troubleshooting when things go wrong.

Is there a device that is sold that will read any error conditions or codes in the Autoride system?

 

[B-train]

A Tech2 scanner or the newest GM software depending on what year you have. TECH2 supports up to 2011 I believe.

 

[Doubeleive]

A Tech2 scanner or the newest GM software depending on what year you have. TECH2 supports up to 2011 I believe.

Tech2 supports up to 2014, but will only show up to 2013 you just choose 13 in that case, actually 10-14 are the same so it doesn't matter

 

[petethepug]

Gotcha, our 08 YXL Denali rode like a dream after the rears were replaced with a new compressor. GM hadn’t enacted their lifetime guarantee back then, but the ride quality, I feel, was far better than Cadillac’s z95 / Magneride system of the same era they added in 09.

As easy as they are to replace in back, lifetime up on your purchase. They’re unpredictable and if you’re Denali operates in Denali vs. SoCal like ours, it will be sooner than later due to the extremes.

Lifetime guarantee is pretty nice when you’ve got weeks or months to a payday and you can yank off a rear bad strut in 10 min, walk into the parts Dept and swap for a new one in 5 minutes. Ship happens. One boulder or 4x4 wood block off a Semi truck can take out any strut in a second.

I getcha on budget and learned fast on how fast Murphy’s Law can get you on mechanicals. As far as Delphi / now BMI info on algorithms for the active struts you may find more info on them from other applications where Ferrari, Audi or Ford used them.

 

[Grady_Wilson]

Thanks for the replies so far.

From all the service records and from everything I have seen on the truck, it was always dealer serviced so it has all AC Delco / BMI parts.
The left rear shock is starting to leak just a little so I wanted to do some research on the entire system before replacing both rears.

And, as I mentioned, I wanted to get a better understanding of how the entire system operates should the truck start to throw any errors.
Troubleshooting is so much easier when you understand how everything operates and works together.

Are there any particular brands of Tech2 scanners that are recommended?
I've had various scanners going all the way back to the OBD I days, so I've had Autel, Launch and Actron scanners along with various blue tooth adapters that connected to the Torque app.
My most used scanner now is my Launch CRP429C.
But, since it is no longer getting updates, and some new scanners come with lifetime updates, I am not adverse to researching and buying another scanner if it will fit my needs with my Denali.

 

[5StarCustmSolutns]

And, as I mentioned, I wanted to get a better understanding of how the entire system operates should the truck start to throw any errors.
Troubleshooting is so much easier when you understand how everything operates and works together.

@Grady_Wilson, did you ever make any progress on this subject??

I have been thinking about this for a couple years now, but after deciding a few months ago to turn my GMT900 into an overweight Luxury Pre-Runner; my Z55 has to go.

I completely understand where these guy are coming from by recommending OE or similar parts. *On the road* the system has been hard to beat for a long time. However, Arnott, and more specifically the cost and warranty of their shocks have been a big part of that. Now, with Arnott deciding to re-nig on their lifetime warranty, and considering the cost of the remaining options, it does take some of the luster away from the idea of sticking with the system!?!?
And I can tell you with the utmost confidence that there are far more capable, better handling shocks available for the cost of official GM replacements.

But since nobody made any attempt to answer your actual question, I'll share what I've been able to learn since yesterday when I started attempting to find the same answers you were seeking:

The Electronic Suspension Control Module sends a specific constant "amount of voltage" to the four Ride Height Sensors. The amount of voltage the sensors return to the ESCM is based on their position. Every mm moved by the sensor changes the signal that leaves the sensor. I just explained it to my buddy an hour ago as: (obviously this isn't exactly how it works, but it helped him get the concept) Imagine the sensor arm having a metal contactor button on the end that moves across a piece of metal that is thicker on one end than the other. When ride height changes enough to swing the button to that certain spot where the thickness of the metal plate creates enough resistance, to then create enough change in the voltage that's leaving the sensor and heading back to the ESCM, the ESCM will then realize the return signal is out of the "acceptable range"...

When the ESCM detects a "significant" change in these two readings that lasts longer than 10 seconds, it turns on the ELC Relay. The ELC Relay then sends a "specific signal" to the Compressor commanding it to Open the Exhaust Valve for 1.5sec to release any built up pressure in the head, and then ether: Sends a different "2nd signal" or as a "second function" of that first signal, activates the Air Comp. And lastly the ESCM will only allow the Air Comp to run for a total of 255 seconds to prevent overheating....

Everything I just typed in "quotes" are the numbers that you would need to activate the compressor on command, IF you were wanting to maintain the Autoride Option AND use the compressor for some aftermarket airbags or your favorite pool inflatable.
But since I am removing my Z55, I am only concerned with the correct ohm resistors to make the ESCM think eveything is OK, and also with the amount of voltage used turn the compressor on so I can inflate my rubber duckys....

And I will gladly let you know what I fond out if you're still interested

 

[SpareParts]

I discovered that after putting a 4in lift on a 2007 Escalade EXT you can actually fine tune the suspension to your liking by making the rods longer or shorter.
Changing them out a few times over a weekend, I was able to make it ride and handle better than ever.
I do not remember if it was Z55 or Z95 but I was able to keep all electronics intact and retain the air leveling portion using rear shock extenders I made myself with 1/4 plate.
On my current ride, I will be keeping the front Z55.
The rear not sure but I will retain an air shock style shock either way using the sensors to control it.
Adds to the conversation. Maybe, maybe not.