Investigations

ELECTRONIC STABILITY CONTROL

NHTSA Engineering Analysis EA09006 — closed, opened 2009-04-08 and involving the TOYOTA SEQUOIA.

EA09006 Engineering Analysis Closed

Vehicle: TOYOTA SEQUOIA View model page

NHTSA investigation EA09006 is a Engineering Analysis opened on 2009-04-08 and currently closed. The subject of record is TOYOTA SEQUOIA, which places this file inside the Office of Defects Investigation queue for TOYOTA. Latest activity on this investigation was logged on 2010-05-12 — NHTSA updates that field whenever an Information Request goes out, a supplement is filed, or a status change is recorded in the public docket.

An Engineering Analysis like EA09006 is the deeper technical phase that follows a PE. NHTSA requests design, warranty, and field-failure data from the manufacturer, conducts its own testing when needed, and determines whether the evidence supports a safety defect finding that would compel a recall.

Investigators summarized the matter as follows: "On April 28, 2010, Toyota Motor North America submitted a Defect Information Report (NHTSA Recall No. 10V-176) to NHTSA describing a problem in the Vehicle Stability Control (VSC) system in approximately 50,000 Model Yea..." 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. Related TOYOTA files, listed below, give context on whether this is an isolated concern or part of a broader pattern across the brand.

Status
Closed
Type
Engineering Analysis
Opened
2009-04-08
Latest Activity
2010-05-12

Investigation Summary

On April 28, 2010, Toyota Motor North America submitted a Defect Information Report (NHTSA Recall No. 10V-176) to NHTSA describing a problem in the Vehicle Stability Control (VSC) system in approximately 50,000 Model Year (MY) 2003 Toyota Sequoia vehicles. According to the report the centering position of the Steering Angle Sensor (SAS) in the MY 2003 vehicles may not be stored correctly due to a logic problem with the Skid Control Computer programming. The VSC system uses the information from the SAS to calculate the driver's intended vehicle direction. This information is cross referenced to sensors that tell the system which direction the vehicle is actually going and the system will, if it determines a variance indicating the vehicle is in a over-steer or under-steer condition, reduce throttle control and apply braking to make a correction in vehicle direction towards what the system believes is the driver's intended path. Toyota dealers will replace the Skid Control Electronic Control Unit in recalled vehicles. Toyota has indicated to NHTSA that it does not believe that inappropriate activations of the VSC system present an unreasonable risk to safety because it believes the activations are rare and tend to occur at low speeds when the vehicle is fully controllable and that the activations do not last more than a few seconds. Based on interviews with complainants ODI believes that the majority of the inappropriate activations of the VSC system occur when turning at low speeds, such as when a driver is pulling into or across the flow of oncoming traffic. Complainants report the effect produced by the malfunction of the VSC system is to leave the vehicle without the ability to accelerate up to speed, essentially leaving them creeping along exposed to oncoming traffic, because of the brake activation and reduction of throttle control caused by the VSC system. Complainants report that the events can last up to 10 seconds and some complaints report that oncoming tra

About This Investigation Type

An Engineering Analysis (EA) is the in-depth phase following a Preliminary Evaluation. NHTSA engineers conduct testing, collect data from manufacturers, and perform detailed technical analysis to determine whether a safety defect exists. An EA may lead to a voluntary recall by the manufacturer or, in rare cases, a mandatory recall order.

Other TOYOTA Investigations

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. Learn more.