how do I replace a power switch for my 2007 grand prix on the front left side ?
The problem is still likely to be the motor. Moving the window down is less stress on the motor as the window drops down (gravity helps). Going up takes more motor torque and an aging motor no longer has the power to push the window up like it did when newer. If the window "tries" to go up but is sluggish or stops, it is not the switch. It may also be an alignment issue causing the window to bind at some point, but I am betting it is the motor.
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