Investigations
LOSS OF ELECTRIC POWER STEERING
NHTSA Preliminary Evaluation PE04031 - closed, opened 2004-03-30.
NHTSA investigation PE04031 is a Preliminary Evaluation opened on 2004-03-30 and currently closed. The subject is tracked inside the Office of Defects Investigation queue. Latest activity on this investigation was logged on 2004-07-01 - 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 PE04031 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: "ODI OPENED PE04-031 BASED ON EIGHT REPORTS OF ALLEGED POWER STEERING FAILURE IN THE SUBJECT VEHICLES. THE COMPLAINTS ALLEGE THAT THE DRIVER SUDDENLY LOST ALL ELECTRIC POWER STEERING ASSISTANCE WITHOUT WARNING MAKING THE..." 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
ODI OPENED PE04-031 BASED ON EIGHT REPORTS OF ALLEGED POWER STEERING FAILURE IN THE SUBJECT VEHICLES. THE COMPLAINTS ALLEGE THAT THE DRIVER SUDDENLY LOST ALL ELECTRIC POWER STEERING ASSISTANCE WITHOUT WARNING MAKING THE VEHICLE DIFFICULT TO STEER. THE SUBJECT VEHICLE UTILIZES AN ELECTRIC POWER STEERING ASSIST SYSTEM (EPS) THAT PROVIDES VARIABLE STEERING ASSISTANCE BASED ON STEERING WHEEL TORQUE, STEERING WHEEL POSTION, AND VEHICLE SPEED. GENERAL MOTORS DOCUMENTS IDENTIFIED THE FOLLOWING TWO FACTORS THAT CONTRIBUTED TO THE ALLEGED DEFECT IN THE SUBJECT VEHICLES: A. CONTAMINATION OF THE TORQUE AND POSITION SENSOR FROM THE SEPARATION OF GREASE APPLIED TO THE STEERING COLUMN ASSEMBLY. B. ELECTRICAL NOISE GENERATED ON THE POWER AND GROUND SLIP RING SURFACES OF THE TORQUE AND POSITION SENSOR. THE NOISE IS GENERATED AS THE SENSOR CONTACT BRUSHES MOVE ALONG THE SLIP RING SURFACES WHEN THE STEERING WHEEL IS ROTATED. ODI'S ANALYSIS SHOWED FAILURE RATES THAT ARE OF CONCERN TO ODI AND INDICATED THAT THE ALLEGED DEFECT IS CONTINUING TO OCCUR IN THE SUBJECT VEHICLES. THIS PRELIMINARY EVALUATION HAS BEEN UPGRADED TO AN ENGINEERING ANALYSIS TO FURTHER INVESTIGATE THIS CONCERN, TO ASSESS THE POTENTIAL SAFETY-RELATED CONSEQUENCES, AND TO DETERMINE THE SCOPE OF THE AFFECTED POPULATION.
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.