Check engine light will not blink

I am sure you are doing it correctly but we just need to make sure. There should be a three pin connector which is for the scan tool. The 2 pin connector is the one that you jump the pins together.

If this is what you are doing then more than likely you have a wiring issue from the connector to the junction center or the ECM. Basically this just completes a circuit from the ECM and causes the light to blink how the ECM tells it too. This means the ECM is able to turn the light on but it is not recognizing the circuit is completed to start flashing the light.

Let me know if this makes sense but I would start with checking to see if the terminals are tight in the connector. They are, you need to measure resistance between the service check connector and the Junction center in the center of the dash. Then the SCC and the ECM.

Let me know if there are questions. Thanks