This will work on most cars with the 16-pin OBD ports (usually located underneath the steering wheel).

However, do this at your own risk. There are chances you could blow a fuse if done incorrectly.

This worked on my 2005 TSX so there's that.

Let's get right into it:

You will need a paper clip. Bend it into a U-shape.

1. Make sure the car is off and the key is not in the ignition and all electronics are off (Radio, Lights, etc.)

2. Find the OBD port and jump/short holes #4 & #9.

3. Insert the key into the ignition and twist to position 2, right before it actually starts to crank. Do not crank it.

4. Wait till all dash lights turn on and turn off.

Now the only lights that remain on will be the error lights.

The lights will flash in two ways: Long and Quick

Count the number of flashes for each type. For instance: 2 Long flashes followed by 3 quick flashes means the code is 2-3 or 23.

Google the code and voila!