2007 Caliber

How hard is the camshaft actuator solenoid valve to change on a 2007 Caliber? I am getting a P0017 engine code on a friends's Caliber and she has asked me to look into it.

it takes about 10 minutes with a 10mm..there is a tsb to replace both solenoids and update the pcm......is he out of 3/36 warranty..

She bought it at a used car lot as is....

Don't know why.

These are right below the valve pans right? One for each side. Do I really need to replace both or is side 1 suffiecent?