Q: Can I Look Up What Trouble Codes Mean?

asked by on

Can I look up what trouble codes mean?

When your Check Engine Light comes on or flashes on the dash for you it is indicating there is a problem in one of the vehicle systems and has set a trouble code stored in one of the modules’ memory. The next course of action you should take is to get the vehicle to a safe stopping location to see if it is safe to continue to drive or the vehicle will need to be towed to a location to get it repaired.

In order to diagnose the Check Engine Light you will need to have the diagnostic trouble codes retrieved from the engine control module (ECM). This module has control over the Check Engine Light and other modules such as the ABS module. The module will request the ECM to turn on the Check Engine Light if needed to alert the driver of a problem in the system that the module monitors.

To get the trouble codes, you would need to hook up a scanner to the OBD connector under the dash or next to the center console on most vehicles. Some vehicles have a dash display that can display codes itself without an external scanner. The scanner will need to be used on most vehicles, though.

After hooking up the scanner and turning it on, you will then have to turn on the ignition key. The scanner may give you one or more options depending on the scanner used. You may have to select the module to scan and should start with the engine first. Once selected, the scanner may ask for you to select diagnostic trouble code (DTC), live data or freeze frame. Select DTC to get codes, live data to look at a sensor reading to help diagnose a code later on, or freeze frame data to see when the last code was set.

Once you select DTC to be retrieved, the scanner will display any codes in the computer memory. The codes should be written down before moving forward with diagnostics. You should then look at the freeze frame data to see when the problem happened and the code was set in memory. This may tell you the speed, temperature, throttle position, and other information to help you in diagnostics of the code. On some cheap scanners it will only give you the code number, but on most better scanners it will give you the code and its meaning. If you have a less expensive scanner then you can do a simple search online for your diagnostic code](https://www.yourmechanic.com/advice/tag/diagnostics). If you do not find your code or need help with the code, then contact a mechanic to come and help you diagnose the DTC you are getting.

The DTC is only part of troubleshooting the code you are getting. I have seen too many misdiagnoses of a problem because someone replaced a component based on the code retrieved only and not on a diagnostic pinpoint test of the code. Have the code pinpoint test performed to isolate the failure instead of a guessing by the code only.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Can I Look Up What Trouble Codes Mean?

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Car started to slow down and then the check engine light, battery, and engine oil light came on. What could cause this?

Hi there. It is possible that the battery cable came loose or the wires to the oil pressure sensor has came loose or failed. Check the battery cables and make sure that the terminals are tight and clean. Check the...

Q: Getting multiple trouble codes

This is a strange group of codes that you have. Most of the time when you get this number of different codes coming up it is due to a voltage issue or a module that is failing. When something like...

Q: Check engine light on & OBD #P0171

P0171 for your car is "system too lean." The most common cause is a vacuum leak and it can come from a leaky hose or a leaky gasket. However, I did a quick search and found someone on the forums...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...