NHTSA Office of Defects Investigation
Preliminary Evaluation PE02-061: ABS TONE RING CORRODES CAUSING UNINTENDE
- Closed
NHTSA's Office of Defects Investigation opened Preliminary Evaluation PE02-061 on August 7, 2002 and closed it on December 11, 2002. NHTSA's investigations file lists the 1996–2002 Freightliner Freightliner for it.
Updated daily from NHTSA's investigations file
Key facts
- NHTSA number
- PE02-061 (also written PE02061)
- 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 December 11, 2002
- Opened
- Closed
- Vehicle or equipment manufacturer
- FREIGHTLINER LLC
- Component
- Service Brakes, Hydraulic — Antilock/Traction Control/Electronic Limited Slip
- Vehicles and equipment
- 1996–2002 Freightliner Freightliner
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 PE02-061.
ODI INITIATED PE02-061 BASED ON TWO REPORTED INCIDENTS IN WHICH FREIGHTLINER VEHICLES EQUIPPED WITH INTEGRAL ABS TONE RINGS HAD EXPERIENCED INCREASED VEHICLE STOPPING DISTANCE.INTEGRAL TONE RINGS INCORPORATE THE ABS TONE RING INTO THE BRAKE ROTOR TO FORM A ONE-PIECE INTEGRATED COMONENT.FREIGHTLINER HAS IDENTIFIED 266 WARRANTY CLAIMS FOR CORRODED ROTORS.SINCE THE ABS TONE RING IS AN INTEGRAL PART OF THE HYDRAULIC BRAKE ROTOR IN THE AFFECTED FREIGHTLINER VEHICLES, CORRODED ROTOR SENSOR TEETH MAY COMPROMISE THE QUAILITY OF THE ABS TONE RING SIGNAL TO THE ABS ECU.A SIGNIFICANT NUMBER OF FREIGHTINER WARRANTY CLAIMS INDICATE THAT HE TONE RING CONDITION WAS DISCOVERED BY SERVICING MECHANICS WHO WERE INVESTIGATING THE CAUSE FOR THE ILLUMINATED ABS WARNING LIGHT.ODI IS CONCERNED AS TO (1) WHETHER VEHICLE OPEERAOTRS ARE SUFFICIENTLY COGNIZANT OF THE IMPORTANCE OF HAVING THE VEHICLE SERVICED IN A TIMELY MANNER IN RESPONSE TO THE ILLUMINATED ABS WARNING LIGHT SINCE THE ABS WARNING LIGHT IS THE ONLY WARNING PROVIDED BEFORE THE VEHICLE STOPPING DISTANCE MAY BE AFFECTED AND (2) QUANTIFYING THE EXTENT TO WHICH STOPPING-DISTANCE IS AFFECTED AND ASSESSING THE ASSOCIATED RISK TO SAFETY. ODI CONDUCTED A PARALLEL INVESTIGATION(PE02-060) OF INCREASED STOPPING DISTANCE ASSOCIATED WITH CORRODED ABS TONE RINGS AT INTERNATIONAL TRUCK.THIS INVESTIGATION WAS CONCLUDED ON NOV 21, 2002 AFTER INTERNATIONAL TRUCK CONCLUDED THAT THE ABS ECU....CAN MISINTERPRET FALSE WHEEL SPEED SIGNALS... AND NOTIFIED NHTSA OF THEIR INTENTION TO CONDUCT A CAMPAIGN (NHTSA 02V-252) TO CORRECT THE AFFECTED VEHICLES.RECOMMENDATION IS TO OPEN AN ENGINEERING ANALYSIS.
Vehicles and equipment listed for this investigation
NHTSA's investigations file lists these vehicles and equipment for Preliminary Evaluation PE02-061. 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.
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.
Free VIN check: decode a VIN to see its year, make and model.
Sources
NHTSA's investigation record for PE02-061
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.