Ford Repair: Ford - No Start - PCM problem ?, calibration code, blown fuse

Question
Firstly, Thanks in advance to any of your insights.   Im facing a no-start situation with my ford.... and whats complicating the matter is that the authorized service shop mechanics really dont know their stuff.   To avoid making a lenghty story of the whole issue, Id like to reach out you on specific questions... 1) If the car's battery is disconnected, will that clear the PCM's error codes ? or is this only effective when the negative terminal is removed, wait for 30 secs and reconnected ?   2)If a PCM has lodged an error code( lets say due to a fault in crankshat sensor), will the car not start unless this code is cleared ? I ask so becoz, when my pcm was placed in another known-good car, that car too would not start !Is that an indicator of bad pcm or just the persistence of the error code in the PCM ?   Thanks again... Any answer would be appreciated."

3) upon connecting the diagnostic tool to PCM, if there is no display, does it indicate the PCM has gone bad ?

Answer
Hello Matt, Is it a Ford Dealer ypu've taken it to? First ? 1) The battery being disconnected will clear any codes. to clear properly leave disconnected about 5 min. 2)If you have a code for a CMP and it is a hard fault code the vehicle will not start. Was the vehicle you put your PCM in the same calibration code for the PCM the same? 3) Check to see If you have a blown fuse on the power point that is where the DTC connector gets its power for the Diagnostic Tool. Hope This Helps Thanks Tony