How Vehicle Diagnostics are Run
With as many as 50 different computer systems controlling your car, the “check engine” light gives only the vague idea that something is wrong. What part of the engine are you supposed to check and what are you even looking for?
The computers run the emissions, safety, and comfort features of your car, which leaves a lot of possibilities. A special tool that connects to your onboard computer can run vehicle diagnostics to point your mechanic in the right direction so they can fix the problem.
Let’s take a quick look at how this tool works and what it tells you about your car.
Run a Diagnostic Test
The check engine light is the result of your car’s self-running diagnostic tests. It just doesn’t tell you on the dashboard which test failed or the problem it detected.
To do that, your mechanic has to plug a diagnostic scanner into the OBD-II port that has been standard in US vehicles since 1996. As a result, the hardware interface available from a place like abritesusa.com should be compatible with your car and the software needed to talk to the onboard computer.
The scanner is looking for malfunctions before they become dangerous and should be able to show measured values or live data on its display. The checks might include
- Problems with the engine or individual components
- Issues with transmission and responsiveness
- Brake responsiveness
- Issues with the exhaust system
- Wear and tear on major components
Translate the Vehicle Diagnostics Codes
Once the scanner is connected, the car’s onboard computer sends it a code that looks like P0301 or B-1402. These OBD codes are standardized across manufacturers, although some makers have their own specific codes that relate to a model’s particular equipment.
The letter at the front tells you the general area of the car where the problem exists — P for powertrain, C for chassis, and so on. The code directs your mechanic to where to start looking for whatever problem led to the code.
Diagnose the Problem
The codes should make it easier and faster for your mechanic to identify the problem and take care of any car repair you need. But while they tell your mechanic where to look, they don’t always tell them the exact problem.
Back to the code P0301, the code means an oxygen sensor had a malfunction in bank one. But it could be the result of a wiring issue, faulty sensor, or even computer error. An experienced tech uses the code as a starting point for tracking down the real issue.
Once the repairs have been made, the mechanic repeats the test to ensure the initial error has cleared up. The before and after nature of testing makes this a great tool as part of regular maintenance and not just when a warning light comes on.
Troubleshooting Engine Trouble
Vehicle diagnostics tests help pinpoint a problem when the “check engine” light comes on and catch any issues early during regular vehicle maintenance. Your mechanic connects a special tool to your engine, and the diagnostic interface pops up a code that points to where to begin with fixing the issue.
If you found this article helpful, be sure to check out others on the site related to cars and vehicle maintenance.