Understanding Diagnostic Trouble Codes

Categories: Airbag Codes, Airbag Module Reset, DIY Auto Tips

Diagnostic trouble codes, also called OBD II Trouble Codes, are a set of codes developed by the Society of Automotive Engineers to help users detect issues with their vehicle. If your vehicle has a potential problem, the diagnostic code that it gives you is essential to narrowing down the source of the issue and limiting any unnecessary tests or diagnostics.

OBD II Trouble Codes

Originally developed to identify faults that may make your emissions go beyond 1.5 times the legal limit, the codes have since been expanded to also include important manufacturer-specific alerts. These alerts provide additional information that is unique to your car’s specific make and model.

As a whole, diagnostic trouble codes are an indispensable tool for helping you react quickly to potential problems with your vehicle so you can get them resolved before they cause larger issues. Understanding what they are and what you should do about them will help you take control of your car’s maintenance and empower you to proactively take part in the diagnostic and repair process.

How to Know You Have a Trouble Code

Your car will warn you when you have a code by turning on the “check engine” light, otherwise known as the Malfunction Indicator Lamp. Your car is equipped with an Onboard Diagnostic System that monitors the processes of your engine, transmission and car body to ensure that everything is working correctly and efficiently. If it is not, the ODS may register a diagnostic code and alert you to it by turning on the check engine light.

However, the check engine light merely alerts you to a possible problem. It does not tell you the diagnostic code that the ODS registered, or whether the problem is minor or a serious safety hazard. Because of this, it is best to always take the situation seriously and find out what problem may have triggered the code as soon as possible by having your ODS scanned.

Scanning for Diagnostic Trouble Codes

While some vehicles have the option to find out diagnostic trouble codes through the onboard dash, for most makes and models it is easier to scan the ODS to find out the problem. If you don’t have a scan tool, as many people wouldn’t, you can have your ODS scanned at most auto supply stores either for free or a low fee. All auto repair shops will also have a diagnostic scanning device. However, they may charge you up to $100 to use it — and that’s just to identify the problem, not fix it.

If the scanner finds one or more trouble codes, it will give you a reading with an alphanumeric number consisting of one letter followed by 4 numbers. Print it out or write it down. This is your diagnostic trouble code and it will help you and your auto technician narrow down what may be causing a problem with your vehicle.

How to Read a Diagnostic Trouble Code

The letter of your trouble code tells you whether the issue was detected in your powertrain, body, chassis, or network communications — signified with either a P, B, C, or U respectively.

The first number of your code will let you know whether the code is a generic code that pertains to all vehicles or whether it is a manufacturer-specific code for your particular make or model. For generic codes, the first number will be a 0 and for manufacturer codes, it will be a 1.

The other three numbers further narrow down where in the system the issue was detected. Together, this alphanumeric combination can create over 5,000 possible codes that could set off your check engine light and alert you to a possible problem.

MyAirbgas Can Help Solve Your Diagnostic Trouble Code

Having a diagnostic trouble code registering in your car’s system will cause your vehicle to fail emissions tests and pollute the environment. Ignoring one could be a serious risk to your car’s internal processes – not to mention the health and safety of you and your passengers.

If you have a diagnostic code that you need help resolving, contact the diagnostic experts at MyAirBags. We can help you understand and solve the underlying issue behind your trouble code. We offer mail-in repair services for parts that are causing your car to register diagnostic codes. Once we receive your part, we can have a new or repaired piece shipped back to you in 24 hours so you can get back on the road quickly and safely.