NHTSA Office of Defects Investigation
Engineering Analysis EA08-009: BRAKE LINE CHAFE
- Closed
NHTSA's Office of Defects Investigation opened Engineering Analysis EA08-009 on April 28, 2008, the day it closed Preliminary Evaluation PE08-002, whose summary cites it, and closed it on December 16, 2009. NHTSA's investigations file lists 5 Mercedes Benz models for it.
Updated daily from NHTSA's investigations file
Key facts
- NHTSA number
- EA08-009 (also written EA08009)
- Investigation type
- Engineering Analysis A more detailed stage of a defect investigation, opened when NHTSA's Office of Defects Investigation decides an issue merits further review, often after a Preliminary Evaluation or a Recall Query; it can include vehicle testing, surveys and further information requests.
- Status
- Closed December 16, 2009
- Opened
- Closed
- Vehicle or equipment manufacturer
- Mercedes-Benz USA, LLC
- Components
- Fuel System, Gasoline — Delivery — Hoses, Lines/Piping, and Fittings; Service Brakes, Hydraulic — Foundation Components — Hoses, Lines/Piping, and Fittings
- Vehicles and equipment
- 5 Mercedes Benz models, including the M-Class and ML430
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 Engineering Analysis EA08-009.
try.vin does not copy NHTSA's investigation documents; NHTSA's investigation record lists the ones NHTSA has published.
ANALYSIS OF COMPLAINTS TO ODI AND MERCEDES AND WARRANTY CLAIM DATA SUBMITTED BY MERCEDES INDICATES THAT THE ALLEGED DEFECT HAS OCCURRED AT A LOW RATE (36.5 COMPLAINTS PER 100,000 VEHICLES AND 0.29 PERCENT WARRANTY CLAIM RATE), WITH NO DISCERNABLE DEFECT TREND INDICATING THAT THE RATE OF CHAFING RELATED BRAKE LINE FAILURES IS INCREASING.THERE HAVE BEEN NO NEW COMPLAINTS SINCE JANUARY 2009.
WHEN THE ANALYSIS IS LIMITED TO INCIDENTS OF BRAKE LINE LEAKAGE THAT RESULTED IN ALLEGATIONS OF REDUCED BRAKE EFFECTIVENESS, THE RATE DROPS EVEN FURTHER (22.3 COMPLAINTS PER 100,000 VEHICLES AND 0.04 PERCENT WARRANTY CLAIM RATE). MERCEDES PROVIDED DATA SHOWING THAT IN THE RARE INSTANCES WHEN CHAFING DID PROGRESS TO BRAKE LINE LEAKAGE THE DRIVER WOULD BE IMMEDIATELY ALERTED TO A PROBLEM BY ILLUMINATION OF THE BRIGHT YELLOW ESP/BAS WARNING LAMP AND CHANGES IN BRAKE PEDAL FEEL.CONTINUED OPERATION WITH A LEAKING BRAKE LINE WOULD RESULT IN ILLUMINATION OF THE BRIGHT RED BRAKE WARNING LAMP AND AN AUDIBLE CHIME DUE TO LOW MASTER CYLINDER RESERVOIR LEVEL. CONTINUED OPERATION WITH THE BRAKE WARNING LAMP ILLUMINATED WOULD ULTIMATELY DRAIN THE RESERVOIR FOR THE AFFECTED CIRCUIT, RESULTING IN LOSS OF THE CIRCUIT AND AN APPROXIMATELY 80% INCREASE IN STOPPING DISTANCES. SURVEYS CONDUCTED BY ODI AND VRTC INDICATE THAT ROUTING ANOMALIES MAY BE MORE COMMON THAN THE COMPLAINT AND WARRANTY DATA SUGGEST FOR THE SUBJECT LINE BUNDLE, WITH LINE CONTACT OR OTHER ROUTING ANOMALY NOTED IN 13 OF 51 VEHICLES SURVEYED BY ODI AND VRTC (25.5%).
WHILE EVIDENCE OF CONTACT BETWEEN THE FUEL LINE AND SUBJECT BRAKE IN A PARTICULAR VEHICLE IS NOT NECESSARILY PREDICTIVE OF EVENTUAL LINE FAILURE/LEAKAGE, SIGNIFICANT CHAFING WEAR WAS NOTED IN TWO SURVEY VEHICLES (3.9%).
TO ADDRESS CONCERNS WITH LINE ROUTING AND ENSURE THAT LINES WITH EVIDENT CHAFING DO NOT PROGRESS TO A LEAK CONDITION, MERCEDES WILL CONDUCT AN OWNER NOTIFICATION PROGRAM INSTRUCTING OWNERS TO BRING THE VEHICLES TO A DEALER FOR A FREE INSPECTION AND REPAIR.LINES THAT DO NOT HAVE A SPACER (RUBBER GROMMET OR OMEGA-CLIP) BETWEEN THE SUBJECT FUEL AND BRAKE LINES WILL HAVE AN OMEGA-CLIP SPACER INSTALLED TO ENSURE ADEQUATE CLEARANCE BETWEEN THE LINES.BRAKE LINES WITH CHAFE MARKS WILL BE REPLACED. ACCORDINGLY, THIS INVESTIGATION HAS BEEN CLOSED. THE CLOSING OF THIS INVESTIGATION DOES NOT CONSTITUTE A FINDING BY NHTSA THAT A SAFETY-RELATED DEFECT DOES NOT EXIST. THE AGENCY WILL CONTINUE TO MONITOR COMPLAINTS AND OTHER INFORMATION RELATING TO THE ALLEGED DEFECT IN THE SUBJECT VEHICLES AND TAKE FURTHER ACTION IN THE FUTURE IF WARRANTED. FOR ADDITIONAL INFORMATION REGARDING THIS ENGINEERING ANALYSIS REFER TO THE EA08-009 CLOSING REPORT.
Vehicles and equipment listed for this investigation
NHTSA's investigations file lists these vehicles and equipment for Engineering Analysis EA08-009. 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.
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.
Mercedes Benz VIN check: decode a VIN to see its year, make and model.
Sources
NHTSA's investigation record for EA08-009
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.