How to Use an OBDII Code Reader

by Katebo

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OBD-II code readers diagnose problems with your vehicle. All vehicles manufactured from 1996 onward are equipped with On-Board Diagnostic II computers. This computer detects error codes and displays warning and service lights on the instrument panel alerting you to have your vehicle checked out and repaired by a mechanic. The codes can be read by an OBD-II code reader and later erased, thus resetting the computer and shutting off the warning and service lights. These code readers are also called scanners and can be purchased from your local auto parts retailer.

Step 1

Find the diagnostic link connector under the driver's side dashboard. This is usually found to the left or right of the steering column. Plug the OBD II scanner into this port.

Step 2

Put the key into the ignition and turn it to the "On" position but don't start the car. This will power on the scanner. Select the command "Read Codes" or a similar type of command.

Step 3

Write down the numerical codes and look them up in the scanner's operation manual.

Step 4

Unplug the scanner and have the vehicle serviced or repaired.

Step 5

Repeat step 1. Put the key back into the ignition and turn it to the "On" position. Select the "Delete Codes" option and wait for the scanner to complete the task. Unplug the scanner.

Start the engine and verify all service and warning lights have shut off.