Skip the auto shop - Our mechanics make house calls
  1. Home
  2. Articles
  3. How Do I Look Up What Different Codes Mean?

How Do I Look Up What Different Codes Mean?

obd scanner

You’re driving your car and everything is going fine when, suddenly, the Check Engine Light comes on. You head home and get out your trusty code reader. You connect it to the OBD II connection under the dash, and the reader displays the code. Now, what does that code mean? You’ve been given a letter or two and a handful of numbers, and possibly even a few words (“cam angle sensor” for instance). What does the code actually mean?

Looking up codes on the internet

The first place you’re likely to turn is the internet. There are tons of websites out there, all promising to help you look up your trouble code and see what it really means. There are a couple of issues here, though.

  • Is it accurate? If you’re looking up diagnostic codes online, what guarantees do you have that the information is accurate? How do you know they’re not just trying to sell you something you may or may not need?

  • How to narrow it down? Most trouble code definitions will tell you the system affected, but not the actual cause of the problem. For instance, a P0100 – Mass or Volume Air Flow Circuit Malfunction code tells you that there’s an issue with the MAF sensor, but has the sensor failed? Is the problem with the wiring? Is the sensor receiving the right voltage?

Looking up codes in manuals

There are manuals available that can walk you through many of the diagnostic codes you’ll pull from your car’s computer, but they’re designed for mechanics (or those with significant mechanical experience), and don’t go into the depth that inexperienced drivers would need in order to accurately diagnose the problem.

Is it really the problem?

You must also consider the fact that the trouble code stored in your car’s computer might have nothing whatsoever to do with the actual problem. For instance, a trouble code with a sensor might not mean that the sensor has failed, but that the wiring harness has been damaged (in this case, replacing the sensor would be a complete waste of both time and money).

The primary thing to remember here is that trouble codes aren’t really the answer. They’re nothing more than a starting point for a professional diagnosis of the actual problem.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

Veteran and Military Driver Laws and Benefits in Idaho
The state of Idaho offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch in the...
Veteran and Military Driver Laws and Benefits in New Mexico
The state of New Mexico offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...


Related questions

Q: Running Rich

Hello...I would hold off speculation on the effect of the exhaust retrofit until you performed the usual diagnostics on the engine issue that you have. Running rich could be due to oxygen sensors, fuel pressure regulation, problems with the air...

Q: Car stalls after water pump, timing belt, plugs, valves replacements

Many different systems can cause a stalling malfunction on your vehicle. The most common are a fuel pump, fuel filter, spark plugs, battery, wiring fault or a crank/cam sensor. If the timing belt slipped off and caused the components to...

Q: Acceleration hesitation in O4-cylinder 2002 Chevy

If you find that when you step on the gas and your RPM takes up, but the car doesn't follow, the transmission is slipping. Unfortunately on that, it's a very expensive job rebuilding the transmission. So what you're going to...