Investigations
AIR LINE DETACHING FROM DASH
NHTSA Preliminary Evaluation PE07050 - closed, opened 2007-10-11.
NHTSA investigation PE07050 is a Preliminary Evaluation opened on 2007-10-11 and currently closed. The subject is tracked inside the Office of Defects Investigation queue. Latest activity on this investigation was logged on 2008-02-01 - 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 PE07050 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: "THIS INVESTIGATION WAS OPENED AFTER ODI RECEIVED NOTIFICATION FROM TWO FLEETS (TOTALING SEVEN COMPLAINTS) ALLEGING THE AIR LINES CONNECTING TO THE DASH AIR GAUGE WERE LEAKING AIR AND SETTING OFF THE LOW PRESSURE AIR BUZZ..." 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
THIS INVESTIGATION WAS OPENED AFTER ODI RECEIVED NOTIFICATION FROM TWO FLEETS (TOTALING SEVEN COMPLAINTS) ALLEGING THE AIR LINES CONNECTING TO THE DASH AIR GAUGE WERE LEAKING AIR AND SETTING OFF THE LOW PRESSURE AIR BUZZER. DURING THE COURSE OF THIS INVESTIGATION, ODI INTERVIEWED THE INVOLVED FLEETS, CONDUCTED FIELD TRIPS TO EXAMINE SIMILAR BUSES, VISITED DEALERS AND REVIEWED DATA FURNISHED BY BLUE BIRD IN RESPONSE TO AN INFORMATION REQUEST. WHILE BIRD BIRD WAS UNABLE TO DETERMINE A DEFINITIVE CAUSE FOR THE REPORTED FAILURES, THEY BELIEVE THE LOW NUMBER OF COMPLAINTS INDICATES AN ANOMALY AND THE LEAKS MAY HAVE BEEN CAUSED BY THE UNINTENTIONAL POSITIONING OF THE HOSE DURING DASH INSTALLATION. BLUE BIRD THEORIZES THAT AS THE 1/4" DASH GAUGE AIR LINE TUBING WAS INSTALLED BEHIND THE DASH, THE TUBING ENTERING THE "PUSH-IN" QUICK DISCONNECT FITTING MAY HAVE BEEN POSITIONED AT AN ANGLE PUTTING STRESS ON THE PLASTIC MOVABLE PART OF THE FITTING. OVER TIME THIS STRESS MAY HAVE CAUSED THE PLASTIC PART OF THE FITTING TO DETERIORATE, RESULTING IN AN AIR LEAK. BASED ON THE RESULTS OF AN AIR BRAKE SYSTEM TEST CONDUCTED BY BLUE BIRD, COMPLETE DISCONNECTION OF THE ¼" AIR LINE AT THE DASH AIR GAUGE DOES NOT DEPLETE THE BRAKE AIR SYSTEM TO THE POINT WHERE THE BRAKES WILL NOT OPERATE AS DESIGNED. THE TEST SHOWED THAT EVEN WITH THE AIR LINE DISCONNECTED, NORMAL OPERATION OF THE BUS WILL CONTINUE TO CHARGE THE AIR SYSTEM RESERVOIR, ALLOWING FOR SAFE OPERATION UNTIL THE BUS CAN BE CHECKED. NEVERTHELESS, ALTHOUGH BLUE BIRD'S TEST DATA AND CUSTOMER INFORMATION CONFIRMS THERE IS NO LOSS OF BRAKES WHEN THE DASH AIR GAUGE LINES LEAK OR BECOME DISCONNECTED, BLUE BIRD INTENDS TO DEVELOP A SERVICE BULLETIN TO INSPECT THIS AIR LINE CONNECTION. THE SERVICE BULLETIN WILL BE SENT TO OWNERS OF ALL 2006 AND 2007 MODEL YEAR BLUE BIRD ALL AMERICAN SCHOOL BUSES. BASED ON THIS INFORMATION, A SAFETY RELATED DEFECT TREND DOES NOT EXIST AT THIS TIME AND FURTHER USE OF AGENCY RESOURCES IS NOT WARRANTED. THE CL
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.