After your last visit to an auto repair shop, you might have wondered why you were charged a fee for “diagnostic services.” Think about it this way: When you visit your doctor for a health problem, you pay the physician to diagnose the ailment and for the tests that go along with it. It stands to reason that you’d pay your local auto service professional a fee to diagnose the problem with your car as well.
So receiving a diagnostic charge for an especially tricky automotive problem shouldn’t come as a surprise. Automotive diagnostics can cover quite a range.
To Check or Not to Check Your Engine?
Much of the confusion comes when the problem involves your vehicle’s check engine light. This light typically comes on when the internal engine management computer senses a problem.
Since 1996, all cars and light trucks in the U.S. are required to use a standardized diagnostic system to help technicians determine what’s wrong with your vehicle. The diagnostic system works with your vehicle’s Engine Control Module (ECM) – the computer that controls many engine functions.
This computer monitors dozens of components and processes simultaneously. Depending on what the sensors read, the computer will make adjustments to compensate for certain conditions and minor problems. When there is an issue that it can’t adequately adjust for, the computer will turn on the check engine light – sometimes called the ‘service engine soon’ light on certain vehicles.
This warning light signals you to have your car serviced soon so technicians can read the trouble code and the problem can be fixed. Your local service center will have a tool with powerful software that should help the technician diagnose the problem.
The Trouble with Trouble Codes
There’s a common misconception among drivers that the trouble code tells the technician exactly what’s wrong. So, why is there a diagnostic charge when the scanner quickly gave the correct diagnosis?
In reality, it’s not that straightforward. The ECM’s trouble code just indicates which engine parameter is out of range – not what’s causing it. The service technician needs to determine the underlying problem that’s causing the malfunction.
An example of a trouble code could be P0133, which reads “Bank 1 sensor 1 circuit slow response.” This means that the front oxygen sensor has a slow response time to changes in the air-fuel mix. If that’s all you knew about cars, you would think your oxygen sensor was broken and would replace it. Now, it could be the oxygen sensor – but it could also be any number of other things.
On the Hunt for an Engine Error
Your service advisor will make a list of the most likely causes and begin tracking down the source of the problem. Unfortunately, this takes time. Kennedy Transmission Brake & Auto Service, like most service centers, subscribes to databases that document possible causes for all possible trouble codes. These essential databases are specific to each vehicle and engine combination.
Some diagnoses are quick and easy; others are more involved, time-consuming, and difficult. Of course, your service technician wants to figure out what’s wrong with your car or truck and get you back on the road as quickly as possible.
Diagnosis: Visit Kennedy Transmission Today
On-board diagnostics provide a powerful starting place for a highly-trained, well-equipped technician to get to the bottom of your problem. When your check engine light comes on, don’t panic. Get it checked soon at your local Kennedy Transmission Brake & Auto Service location.
Note: A flashing check engine light means that there is a severe engine problem. Get in as soon as you can – waiting too long can lead to very expensive damage.
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