HOW TO RETRIEVE "CHECK ENGINE" [CEL] CODES

If your CEL has illuminated, it is far more helpful to know WHY it has lit up instead of just guessing at the problem.

How do you find out what the error is?
Well you will need a short piece of wire or a paperclip.

On the passenger side of your car, under the dash beneath the glove box, you will find a green cover above the kickpanel that houses a blue connector that has two wires.
[spoiler="Pics"]

Images by c-speedracing.com[/spoiler]

PART ONE: RETRIEVING THE CODE(S):
1. Turn the ignition off and use the piece of wire or paperclip to jump the blue connector, so that you connect the two wires together.
Stick one end of the paperclip or piece of wire into one prong on the connector and stick the other end of the paperclip or wire into the other prong.

2)Turn the key to the IGN position and watch your CEL light.
It will illuminate in a series of flashes.

3) Record the CEL lamp flash pattern.
You will notice that there will be LONG flashes and SHORT flashes.
All of the ECU trouble codes are two-digits.

PART TWO: DECODING THE FLASH PATTERN:
LONG flashes determine the TENS digit by the number of times it flashes.
SHORT flashes determine the ONES digit by the number of times it flashes.

As an example:
LONG-LONG-LONG
followed immediately by
SHORT-SHORT-SHORT-SHORT-PAUSE
is the trouble code: 34

If the ECU has logged only one code, then the pattern of flashes will simply repeat until you remove the key.

If more than one ECU error code has logged, then you will see a different series of flashes followed by the long pause.

Once all the ECU codes have been displayed, they will continuously cycle until you remove the key.

As an example:
LONG-LONG
followed immediately by
SHORT-PAUSE
followed by
LONG-LONG-LONG-LONG
followed immediately by
SHORT-SHORT-SHORT-PAUSE
indicates the trouble codes: 21 and 43

Once you have determined the codes, you can simply remove the paperclip or wire from the connector and replace it back in the green housing.