CarMD has compiled the industry’s most comprehensive database of diagnostic trouble codes and repairs for “check engine” – related problems downloaded by automotive technicians and vehicle owners since 1996. The data for the CarMD® Vehicle Health Index™ was procured from CarMD’s network of thousands of independent and original equipment automotive service excellence (ASE)-certified technicians who have input and validated failures and fixes into the CarMD diagnostic database from 1996 to current.

CarMD Vehicle Health Index

The data for the April 2012 CarMD® Vehicle Health Index™ was procured from CarMD’s network of thousands of automotive service excellence (ASE)-certified technicians who have input and validated failures and fixes into the CarMD diagnostic database since January 1, 1996. The data for the most current Index was pulled and analyzed between Jan. 15, 2012 and Feb. 13, 2012.

Virtually all 1996 to 2010 makes and models of cars, light trucks, minivans and SUVs – foreign and domestic – with on board diagnostic second generation (OBD2) technology are included in the Index. Those makes and models with more registered vehicles on the road may have a larger statistical weighting in the index findings, as will those vehicles that experience more failures.

In addition to diagnostic trouble code data, CarMD has compiled the most comprehensive database of “fixes” or recommended repairs that correspond to each trouble code scenario. The April 2012 Index statistically analyzes roughly 164,000 fixes and 151,000 diagnostic trouble code scenarios. Each scenario and fix has also been reviewed and validated by CarMD’s internal team of ASE-certified technicians and then output based on a probability algorithm that takes into account the vehicle’s year, make, model, mileage, zip code, DTCs and similar vehicle problems to produce a most likely fix. Because the data stems from those U.S. vehicle owners and automotive technicians who elected to use the diagnostic devices and upload data into the CarMD database, no estimates of theoretical sampling error can be calculated.

CarMD U.S. State Index

For the state Index data, released in June 2011, all 50 U.S. states, plus the District of Columbia, are represented. The states with larger registered vehicle populations and participating ASE certified may have a larger number of DTC and fix scenarios, however, all have been averaged into the overall Index findings. The data in the Index is applicable to more than 80 percent of the vehicles on the road, giving a unique perspective on vehicles driven in the U.S.

The 2011 CarMD State-by-State ranking of average repair costs was derived from analysis of roughly 80,000 repairs made from Jan. 1, 2010 through Dec. 31, 2010 by CarMD’s network of Automotive Service Excellence-certified technicians. The Census Regions and Divisions of the U.S. map was used for regional data calculations. The repairs are all related to a vehicle’s “check engine” system, which is designed to alert drivers to large and small problems that affect emissions output and drivability. This technology is standard on all vehicles manufactured since 1996 and covers an estimated 80% of systems on cars, trucks, SUVs and minivans – foreign and domestic. The CarMD database and average cost of repair findings does not include repairs of problems that are not associated with a vehicle’s on-board diagnostic computer such as tires, brakes and mechanical parts such as belts and hoses.

CarMD Manufacturer & Vehicle Index

The 2011 Index statistically analyzes more than 325,000 specific repairs that apply to roughly 136 million model year 2001 to 2011 vehicles, taking place during the Oct. 1, 2010 to Oct. 1, 2011 time period. The data for the 2011 CarMD® Vehicle Health Index was pulled, analyzed and validated between Oct. 1, 2011 and Oct. 19, 2011, by CarMD’s internal team plus third party experts. The Index is based on downloaded information from each vehicle’s government-mandated onboard diagnostic computer, combined with uploaded repair information from CarMD’s network of automotive technicians. Repair costs are based on original equipment retail MSRP plus 10% markup. Labor rates are procured from several sources, including the Undercar Digest National and Regional Hourly Shop Labor Rate reports, as well as the average amount of time required for each repair. Both are updated annually.

Virtually all 2001 to 2010 makes and models of cars, light trucks, minivans and SUVs – foreign and domestic – with on board diagnostic second generation (OBD2) technology are included in the Index. For the 2011 Vehicle Health Index, CarMD focused on model year 2001-2011 vehicles, since the average age of a vehicle is now just over 10 years old, and these are the vehicles that will be of interest to new and used car buyers. In determining the Top 100 vehicles, CarMD included all makes and models that were listed among the U.S. vehicle population, according to R.L. Polk data, and had a CarMD diagnostic report. In determining the Top 10 manufacturers CarMD included all makes and models that account for at least 1% of the U.S. vehicle population, according to R.L. Polk data. For the Top 10 manufacturers, brands were grouped under their parent manufacturer (i.e. Lexus under Toyota; Acura under Honda; Buick, Chevrolet, Cadillac, GMC, Oldsmobile, Pontiac and Saturn under GM; etc.) The data in the Index is applicable to more than 80 percent of the vehicles on the road, giving a unique perspective on vehicles driven and repaired in the U.S. In determining the most common repairs by manufacturer, this Index looked at the entire OBD2 vehicle population (1996-current) vehicles for each manufacturer from Oct. 1, 2010 – Oct. 1, 2011.

Repair costs are based on retail MSRP plus 10% markup. Labor rates are procured from several sources, including the Undercar Digest National and Regional Hourly Shop Labor Rate reports, as well as the average amount of time required for each repair. Both are updated annually.

CarMD has contracted with a third party web-based project management company to create and maintain the database for compiling and generating this Index. In most cases, percentages were rounded to the nearest tenth. In the instances of a tie for most common fix, DTC or type of failure, percentages were expanded by rounding to the nearest 100th.

For the manufacturer and vehicle rankings, the company programmed a formula that factored in the number of registered vehicles on the road for each manufacturer, make, model and year. A CarMD Vehicle Health Index rating was then assigned using the total number of red reports (or failures) per vehicle (or manufacturer) divided by the total number of vehicles in the population. Percentage of problems and average repair costs have been equally weighted in the CarMD Overall Index rating. The overall Index ranking for the Top Ranked Manufacturers and Vehicles were derived by the average of the Index and cost ranking scores.

On a daily basis, CarMD’s nationwide network of thousands of OE (original equipment) and independent automotive repair technicians recommend, confirm and upload repairs and costs by region to the CarMD database. As a result, subsequent CarMD Vehicle Health Index reports will draw from a larger sampling of diagnostic trouble codes, expert fixes and repair costs. Methodology will remain as defined above.