2004 GMC Envoy PCM Replaced

[Luvlylane]

What causes the emc to have to be replaced in 2004 gmc envoy

[ProTech]

Usually an internal failure will require the PCM to be replaced in any vehicle. Depending on what trouble codes you had stored, they can lead to PCM replacement as well.

Or, if the technician was unable to communicate with the PCM, that can be cause for replacement as well.

There are lots of reasons that can determine if the PCM needs replaced or not, so I can't really give you a specific answer.