NHTSA Office of Defects Investigation
Preliminary Evaluation PE05-009: VACUUM BRAKE BOOSTER FAILURE
- Closed
NHTSA's Office of Defects Investigation opened Preliminary Evaluation PE05-009 on February 10, 2005 and closed it on June 15, 2005. NHTSA's investigations file lists the 2004 Lexus RX330 for it.
Updated daily from NHTSA's investigations file
Key facts
- NHTSA number
- PE05-009 (also written PE05009)
- Investigation type
- Preliminary Evaluation The first stage of most defect investigations: NHTSA's Office of Defects Investigation gathers basic information about a possible safety defect, including from the manufacturer.
- Status
- Closed June 15, 2005
- Opened
- Closed
- Vehicle or equipment manufacturer
- Toyota Motor Corporation
- Components
- Service Brakes, Hydraulic; Service Brakes, Hydraulic — Foundation Components; Service Brakes, Hydraulic — Foundation Components — Master Cylinder; Service Brakes, Hydraulic — Power Assist; Service Brakes, Hydraulic — Power Assist — Vacuum; Service Brakes, Hydraulic — Power Assist — Vacuum — Hoses, Lines/Piping, and Fittings
- Vehicles and equipment
- 2004 Lexus RX330
A recall appears here only when NHTSA's investigations file links one to the investigation; NHTSA's summary or record can name others.
NHTSA's summary
As NHTSA's Office of Defects Investigation wrote it for Preliminary Evaluation PE05-009.
ON FEBRUARY 10, 2005, THE OFFICE OF DEFECTS INVESTIGATION (ODI) OPENED A PRELIMINARY EVALUATION TO INVESTIGATE ALLEGED LOSS OF BRAKE POWER-ASSIST IN CERTAIN 2004 MODEL YEAR (MY) LEXUS RX330 VEHICLES BUILT THROUGH APPROXIMATELY JUNE 30, 2004.
THE SUBJECT VEHICLES WERE MANUFACTURED AT TOYOTA MOTOR MANUFACTURING CANADA, INC.?S CAMBRIDGE, ONTARIO ASSEMBLY PLANT AND WERE EQUIPPED WITH VACUUM BRAKE BOOSTER ASSEMBLIES SOURCED FROM AISIN SEIKI CO., LTD (AISIN) SUBSIDIARY ADVICS NORTH AMERICA, INC. (ADVICS-NA).
TO DATE, ODI IS AWARE OF 146 NON-DUPLICATIVE REPORTS THAT ALLEGE LOSS OF BRAKE POWER-ASSIST AND 6 CRASHES ALLEGEDLY CAUSED BY LOSS OF BRAKE POWER-ASSIST (RESULTING IN 1 MINOR INJURY) ON THE SUBJECT VEHICLES.THE SUBJECT VEHICLES USE A CONVENTIONAL BRAKE BOOSTER ASSEMBLY THAT CONTAINS A RUBBER DIAPHRAGM TO SEPARATE THE FORE AND AFT PRESSURE CHAMBERS.THE OUTER EDGE OF THE RUBBER DIAPHRAGM IS HELD IN PLACE VIA A RETAINING GROOVE ON THE BRAKE BOOSTER BODY.IF THE BOOSTER LOSES VACUUM (E.G., OPERATOR DEPLETES THE VACUUM BY PRESSING THE BRAKE PEDAL SEVERAL TIMES WHILE THE ENGINE IS OFF), IT MAY CAUSE THE DIAPHRAGM TO DEFORM IN THE AREA OF THE RETAINING GROOVE TO THE POINT THAT INSUFFICIENT SEAL EXISTS BETWEEN DIAPHRAGM AND BOOSTER BODY, THUS CAUSING A MOMENTARY LOSS OF BRAKE POWER-ASSIST.THE ADVICS-NA SUPPLIED DIAPHRAGM HAS SLIGHTLY DIFFERENT MATERIAL PROPERTIES COMPARED TO THE DIAPHRAGM INSIDE BRAKE BOOSTERS SUPPLIED BY ADVICS JAPAN, CORP. (ADVICS-J) AND USED ON 2004MY LEXUS RX330 VEHICLES MANUFACTURED AT TOYOTA MOTOR KYUSHU, INC.?S ASSEMBLY PLANT.THE SOFTER RUBBER USED IN THE ADVICS-NA DIAPHRAGM ALLOWS GREATER DEFORMATION AND IS LESS RESILIENT WHEN COMPARED TO THE ADVICS-J DIAPHRAGM.LOSS OF BRAKE POWER-ASSIST MOST OFTEN OCCURS AT VEHICLE START-UP AND APPEARS TO BE MORE PREVALENT IN COLDER TEMPERATURES.MOST OWNERS REPORT THAT BRAKE SYSTEM OPERATION RETURNS TO NORMAL WITHIN A FEW SECONDS AFTER VEHICLE START-UP.TESTING CONDUCTED BY THE MANUFACTURER INDICATES THAT THE ADVICS-NA DIAPHRAGM?S REDUCED ABILITY TO RETURN TO SHAPE IS EXACERBATED BY COLDER TEMPERATURES AND THAT LOSS OF BRAKE POWER-ASSIST AT START-UP MAY LAST FOR A MAXIMUM OF 95 SECONDS AT TEMPERATURES BELOW ?20 DEGREES CELSIUS.HOWEVER, THE SUBJECT VEHICLES HAVE A BACK-UP SYSTEM THAT CAN SENSE A LOSS OF BRAKE POWER-ASSIST AND ENABLE THE ABS ACTUATOR FOR BRAKE HYDRAULIC PRESSURE SUPPORT (I.E., BRAKE PEDAL FORCE ASSIST).
THE MANUFACTURER WILL CONDUCT A SERVICE CAMPAIGN (LEXUS SPECIAL SERVICE CAMPAIGN #5LA) TO REPLACE THE VACUUM BRAKE BOOSTER ASSEMBLY ON ALL AFFECTED SUBJECT VEHICLES.THE ACTION TAKEN BY THE MANUFACTURER IS SUFFICIENT TO RESOLVE THE ISSUES RAISED BY THIS INVESTIGATION.ACCORDINGLY, THIS INVESTIGATION IS CLOSED.THE CLOSING OF THIS INVESTIGATION DOES NOT CONSTITUTE A FINDING BY NHTSA THAT A SAFETY-RELATED DEFECT DOES NOT EXIST.THE AGENCY WILL TAKE FURTHER ACTION IF WARRANTED BY THE CIRCUMSTANCES.
Vehicles and equipment listed for this investigation
NHTSA's investigations file lists these vehicles and equipment for Preliminary Evaluation PE05-009. A listed model year means only that an investigation names it; it says nothing about any particular vehicle. Model years with a try.vin recall page link to that page's NHTSA investigations section.
Lexus
Lexus RX330
What an NHTSA investigation is
NHTSA's Office of Defects Investigation (ODI) looks into possible safety defects in vehicles and equipment, often after owner complaints. An investigation usually starts as a Preliminary Evaluation, or as a Recall Query when it concerns whether an existing recall covers the right vehicles or fixes the problem, and ODI can upgrade it to a more detailed Engineering Analysis. A Defect Petition asks NHTSA to open an investigation, and Audit and Equipment Queries are administrative investigations into whether companies complied with federal vehicle safety requirements, such as reporting, recall and certification rules.
An open investigation is not a finding that a safety defect exists, and NHTSA can close one without a recall.
To see whether a specific vehicle has an open recall, enter its VIN at nhtsa.gov/recalls.
Lexus VIN check: decode a VIN to see its year, make and model.
Sources
NHTSA's investigation record for PE05-009
Investigation details come from NHTSA's investigations file, which try.vin imports once a day. The investigation types are described from the U.S. Department of Transportation Inspector General's May 2023 report on NHTSA's Office of Defects Investigation, NHTSA's petition rules (49 CFR Parts 552 and 557) and NHTSA's Office of Defects Investigation procedures. How try.vin reads NHTSA investigations.