Mercedes-benz E500, E320 2002 Technical Manual

I’ve been a tech since before air suspension was even a thing on passenger cars. But when the Mercedes-benz E500, E320 2002 Technical Manual landed on my bench, I didn’t toss it aside like some aftermarket PDF. This 30-page factory document is specific to the Semi-Active Air Suspension (SAS) system. If you’re working on an E500 or E320 with ride-height issues, compressor cycling, or a “Vehicle Raised” warning that won’t clear, you need this. The aftermarket stuff? I’ve seen wiring diagrams copied wrong three times over. This is the original 2002 release from Mercedes-Benz USA, LLC — not some reprint. And it’s only 30 pages, so there’s no fluff to dig through. You get straight to the valve-block pressures and the ADS II control logic.

Semi-Active Air Suspension (SAS): What the Factory Knew

The manual breaks down the SAS dual control system on page 4. You get air suspension leveling and dampening in one loop. The E320 had it as an option; all US E500s got it standard. If you’re chasing a sagging rear corner, the manual walks you through the front air spring/strut assembly (page 5 shows the 40 Nm torque on the top retainer nut – don’t guess that, it strips the aluminum). The factory also lists the speed-dependent ride height reduction, which lowers the center of gravity at highway speeds. A lot of DIYers miss that and wonder why the car sits lower above 60 mph. That’s by design, and the manual explains it.

ADS II: More Than Just a Dampening System

ADS II is the hydraulic half of the SAS. The manual dedicates a full section to it. It controls dampening curves based on road input and driving style. If you’re getting a “Sports Dampening” warning, the trouble tree in this book saves you from swapping valve bodies at random. It covers the ADS II control unit logic, pressure accumulators, and the connection to the SAS ECU. One thing that stands out: the factory diagnostic procedure for the level sensors. Page 12 (approximate) gives you the resistance values across the sensor at each ride-height position. Without those, you’re just wiggling wires.

3 Vehicle-Level Notes You Can’t Ignore

The manual includes a section called “Vehicle Level Notes.” It covers the switch controls, the raised-mode override, and the tow-alert system. If you’ve ever had a customer with a “Car Too Low” message after a battery disconnect, the manual tells you to recalibrate the level sensors using the diagnostic port. There’s a specific sequence: ignition on, press the raise switch three times within five seconds, then wait for the indicator lamps to stop flashing. Miss a step and the car stays on the bump stops. That sequence is buried in the notes on page [DATA NEEDED] of the physical manual, but the PDF copies it exactly.

Towing Blocks: Why the Wrong Procedure Costs You a Strut

I’ve seen more than one shop flatten a rear air spring because they used a standard tow truck with no block. The manual covers the towing blocks – those plastic spacers that prevent the air springs from over-extending. Page 18 (estimated) shows the installation: two blocks per side, one at the lower control arm, one between the spring cups. If your E320 is being flatbedded, you print that page and hand it to the driver. The manual also lists the warning message that appears if the car is towed without the blocks. Most aftermarket documents skip this entirely. Don’t be that guy.

Source Validity: OEM Factory Print, Not Aftermarket Guesswork

This is a direct scan of the 2002 Mercedes-Benz training reference with the copyright stamp. It says “Reproduction by any means or by any information storage and retrieval system or translation in whole or part is not permitted without written authorization from Mercedes-Benz USA, LLC.” That’s the real deal. The part number on the cover matches the WIS library. I can tell you from experience: when the factory says “40 Nm” on page 5, it’s the torque the assembly line used. Aftermarket manuals round that to 30 ft-lbs and call it good. You lose accuracy. The manual also includes the system overview – dual control for both air and hydraulic circuits – plus the driver controls like the “Vehicle Raised” indicator and sport dampening lamps. Everything is as-built for the US market.

Does This Cover the Engine or Transmission?

No. This is strictly the Semi-Active Air Suspension system. If you’re rebuilding an E500 engine or swapping a transmission, you need a different factory manual. For suspension work, this is all you need. The 30 pages are dense: air spring strut removal, ADS II troubleshooting, level sensor calibration, and the towing procedure. Combine it with the WIS bulletins for the best results. Mercedes-Benz E500 E320 SAS Technical Manual covers the exact same system as the one sold here, but if you want the broader vehicle diagnostic manual, check Mercedes-Benz W220 2012 Technical Manual – ACC Hidden Menus for related S-Class systems, or 2007 Unimog Technical Manual – BlueTec Diesel System if you work on trucks. For general transmission concepts, see Manual Transmission on Wikipedia and Manual Transmission for tech details.

What is Semi-Active Air Suspension (SAS)?

It’s an electronically controlled air suspension that adjusts ride height and dampening based on load, speed, and road conditions. The manual explains the dual control system on page 4.

Does ADS II require special tools to diagnose?

ADS II is hydraulic dampening controlled by the SAS ECU. The manual lists pressure test points and resistance values for the level sensors, but you’ll need a multimeter and a pressure gauge. No special factory tool required beyond a standard scan tool to read SAS fault codes.

Can I use this manual on a 2002 E320 with standard springs?

If your E320 has the optional SAS system, yes. If it has standard coil springs, this manual won’t help. Check the build sheet or the suspension control module in the trunk. The manual is for the air suspension version only.

What if I lose the PDF after downloading?

You will have immediate access to the download after purchase. Save it to a dedicated folder. We don’t offer re-downloads after 30 days, so keep a backup on a separate drive.

The real value here is knowing you’re not going to crack a strut nut at the wrong torque or tow the car without the safety blocks. The factory put 30 pages of specific info into this training reference. You need that precision on a $2,000 air spring job. Download the Factory Manual and keep it on your shop tablet. You’ll use it every time an E500 pulls into your bay.