The manual for the XCal2 says to pull the fuses for the fans before uploading a program. The first time I did it I pulled the fuses that it recommended, but the second time I forgot. I didn't have any problems...I'm just curious if you really need to do this for future reference?

 

I didn't pull any fuse when I did my re-flash. I had the same question and everybody told me that it's not neccassary.

 

On my Crown Vic, the fuel pump fuse should be pulled to prevent the fuel from pumping continuously. Also the IAC would engage during the flashing.

If you don't hear anything odd when you flash the S197 with the X-Cal 2, don't worry about it.

 

Pulling the fuse is not necessary. I have, as well as others, reflashed numerous times without any problems.

 

Pulling the fuses is only required for less than fully charged batteries and for 99-04 Stangs

 

me too

 

I hear it on my GT. But AFAIK, it has not caused any problems.

 

Didn't have to here either. No problems.

 

I asked Doug this exact question a while back. He said it's not necessary on our Mustangs and that it mainly applied to other Ford models where a re-flash can take several minutes.

 

From my experience, the X-Cal 2 takes only 30 seconds to program using your laptop, and it takes 1 minute to flash the PCM (I used the X-Cal 2 on my Crown Vic for awhile).

The older 9100 microtuner (the blue SCT tuner) takes 1 minute to program using the laptop, and 5 minutes to flash the PCM. The 9100 is no longer supported/used by SCT for various reasons. I actually still use my 9100 for the Crown Vic.

On my 00 Crown Vic, the fuel pump and IAC would constantly run when the PCM was being flashed. You can hear the fuel gushing through the fuel rail (mechanical return system) and the IAC "buzzing" at a high pitch. My air compressor would also occasionally fire up if the air springs were deflated.

On the 05-up Mustang GTs, we have an electronic returnless fuel system and a drive by wire electronic throttle control. There is no IAC and the fuel pump should not be running. It should only take 1 minute to flash the PCM using the X-Cal 2, but nonetheless it is a good idea to hook up a battery charger just in case...