Investigations
AIR SUSPENSION SYSTEM FAILURE
NHTSA Preliminary Evaluation PE07042 - closed, opened 2007-08-14.
NHTSA investigation PE07042 is a Preliminary Evaluation opened on 2007-08-14 and currently closed. The subject is tracked inside the Office of Defects Investigation queue. Latest activity on this investigation was logged on 2007-11-20 - NHTSA updates that field whenever an Information Request goes out, a supplement is filed, or a status change is recorded in the public docket.
A Preliminary Evaluation like PE07042 is the entry point of the federal defect-investigation process. NHTSA engineers scan complaint databases, field reports, and manufacturer data to decide whether an Engineering Analysis is warranted, whether a voluntary recall is already sufficient, or whether the pattern does not rise to a defect finding.
Investigators summarized the matter as follows: "THE SUBJECT S-CLASS VEHICLES CONTAIN A COMPRESSED AIR SUSPENSION SYSTEM THAT USES AIR STRUTS ON EACH OF THE FOUR WHEELS IN LIEU OF TRADITIONAL SPRINGS AND SHOCK ABSORBERS. THESE AIR STRUTS USE COMPRESSED AIR TO SUPPORT T..." Investigations are the early-warning layer of the federal auto-safety system, sitting upstream of formal recalls and defect orders. Whether this one closes without action or escalates into an Engineering Analysis, the full history stays in the ODI archive so researchers, litigators, and buyers can pull the paper trail at any time.
Investigation Summary
THE SUBJECT S-CLASS VEHICLES CONTAIN A COMPRESSED AIR SUSPENSION SYSTEM THAT USES AIR STRUTS ON EACH OF THE FOUR WHEELS IN LIEU OF TRADITIONAL SPRINGS AND SHOCK ABSORBERS. THESE AIR STRUTS USE COMPRESSED AIR TO SUPPORT THE WEIGHT OF THE VEHICLE AND CONTROL RIDE HEIGHT. IN THE EVENT OF THE LOSS OF AIR FROM THE SYSTEM, AN ALERT WILL FLASH ON THE INSTRUMENT CLUSTER WARNING THE DRIVER TO EITHER DRIVE CAREFULLY OR TO STOP THE VEHICLE. THE VEHICLE RIDE HEIGHT CAN BE REDUCED BY AS MUCH AS 105 MM BELOW NORMAL RIDE HEIGHT BEFORE THE FULL LOAD OF THE VEHICLE FOR THAT WHEEL COMES TO REST ON A STEEL ROD, WITH A RUBBER STOP ON THE END, LOCATED IN THE SHOCK ABSORBER. THIS REST-STOP CONDITION IS DESIGNED SUCH THAT THERE IS NO IMPACT ON VEHICLE CONTROL. MERCEDES-BENZ (MBUSA) SUPPLIED VIDEO SHOWING A VEHICLE IN THIS CONDITION OPERATING UNDER SEVERAL DIFFERENT SITUATIONS INCLUDING EVASIVE MANEUVERS DEMONSTRATING THE ABILITY OF THE VEHICLE TO BE CONTROLLED EFFECTIVELY WITH A RIDE HEIGHT REDUCED TO THE MINIMUM. ONLY THOSE COMPLAINTS TO ODI AND MBUSA THAT ALLEGED A STEERING INTERFERENCE DURING A REDUCED RIDE HEIGHT CONDITION WERE COUNTED IN THIS RESUME FAILURE REPORT. SOME COMPLAINTS ALLEGED THAT WITH A REDUCED RIDE HEIGHT AND A "STOP NOW" WARNING MESSAGE THERE WAS A RUBBING NOISE WHEN TURNING, BUT THE ABILITY TO STEER THE VEHICLE WAS NOT COMPROMISED. A SAMPLING OF WARRANTY CLAIMS SUBMITTED BY MBUSA DID NOT REVEAL ANY INDICATING A LOSS OF CONTROL DUE TO AN AIRMATIC SYSTEM FAILURE. THERE WAS ONE CRASH REPORTED BY MBUSA TO ODI BUT THE INFORMATION AVAILABLE INDICATED THAT IT RELATED TO SUSPENSION SYSTEMS AND IT WAS NOT POSSIBLE TO VERIFY THAT THE INCIDENT WAS RELATED TO AN AIRMATIC SYSTEM FAILURE. FURTHER USE OF AGENCY RESOURCES IN THIS MATTER DOES NOT APPEAR TO BE WARRANTED. THE AGENCY WILL CONTINUE TO MONITOR COMPLAINTS AND OTHER INFORMATION RELATING TO THE ALLEGED DEFECT IN THE SUBJECT VEHICLES AND WILL TAKE FURTHER ACTION IN THE FUTURE IF WARRANTED. THIS PRELIMINARY EVALUATION IS CLOSE
About This Investigation Type
A Preliminary Evaluation (PE) is the first phase of NHTSA's investigation process. It is opened when the agency identifies a potential safety defect pattern, usually triggered by consumer complaints, manufacturer reports, or field monitoring. During a PE, NHTSA gathers information to determine whether a formal engineering analysis is warranted.
Data from NHTSA Office of Defects Investigation. Cross-references: NHTSA recall campaign API and NHTSA FARS where fatality records overlap. PlainCars does not rate or recommend vehicles. about how PlainCars sources NHTSA data.
Read our methodology - how this data is sourced, computed, and verified.