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.
That you need to do is turn the ignition off, and using the piece of wire or paperclip, jump the blue connector so that you connect the two wires together. Basically stick one end of the paperclip or peice of wire into one prong on the connector and stick the other end of the paperclip or wire into the other prong.
Once you have done this, turn the key to the IGN position and watch your CEL light. It will illuminate in a series of flashes.
You will notice that there will be LONG flashes and SHORT flashes. All of the ECU trouble codes are two-digits. LONG flashes determine the TENS digit by the number of times it flashes, and SHORT flashes determine the ONES digit by the number of times it flashes.
...is the trouble code: 34
3 LONG flashes followed by 4 short flashes, then a long pause. If that is the only code the ECU is throwing, then the code will simply repeat until you remove the key. If, however there are more than one ECU error code, 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.
...is the trouble code: 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.
So now you have the codes, what good are the numbers? What do they mean?
Refer to the CEL TROUBLE CODES section.