Join Date: Dec 2008
Location: Tyler, TX
Thanked 407 Times in 347 Posts
Re-flashing the PCM (Powertrain Control Module) can be a variety of things. To explain as best that I can....
The vehicle's PCM has a "base program", much like you PC (Windows). There are many different versions of this base program (Windows), like 06E17 (Win95, 98, XP) etc.
Some software (tunes, etc) will work on multiple base program versions (Win98/XP), most however, will not. When you "upgrade" the base software on the PCM (PC/Laptop), some old functions no longer work.
With SCT tuners, as long as you keep the same "base program" (Win98, or XP for example), the tuner will still work. If, during the reflash, the base program is updated (like from Win98 to XP) the tuner will cease to function.
Many times the "reflash" is nothing more than a minor software update that changes some feature or function in the base software (like a Windows security patch). These do not affect the base program compatability at all.
Does that help?
'93 F-250 HD, 7.3L IDI, 5spd - FARM TRUCK
I Support: Trailer brakes an every axle over the towing vehicle's GVW; CDLs for RVers; Safety inspections for ALL vehicles and 6 axle trucks (97K GVW proposal).
Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote - Benjamin Franklin
I vote for LIBERTY!