1993 Toyota 4Runner Engine Diagnostic tests

I recently purchased a tool to perfom a basic review of any service codes necessary for my 3.0 V6 engine. The tool worked perfectly, revealing the same codes produced when I took the truck to the local dealership for a diagnostic test. The service codes revealed problems with the Mass Air-flow meter, O2 sensor and Intake Air Temp Sensor. The MAF and O2 sensors have been replaced and I am awaiting delivery of the IAT sensor. Per the instructions that came with tool, the procedure for resetting the Emissions computer is to pull the 15A fuse for 30 secs, warm up the engine and retest the engine diagnostics. When I perform these steps, and upon placing the tool in it correct diagnostic position, the Check Engine light flashes continuously without any pauses. Can you share any light as to what has happened?

Thanks,
Frank