Hit the button that ‘may’ heat your mirrors. While they are heating up drive to 7-11. Buy yourself a Slurpee (flavor doesn’t matter). Flick a little Slurpee onto the fully heated mirror. If it melts then your good. Then post a thread in General Care and Detailing section to as: “How do I get Slurpee off of my mirror.”

 

it must be electric.
the ice on my mirrors is melted to water way before the temp of the air coming from the vents in the cab gets warm.

oaw

 

Look at the dash...on the climate control there should be two buttons. One with a little square windows on it, and one with a stick on the left side. The latter is the heated mirrors button. Mines got a button for the regular function, and a seperate on for mirrors.

 

I don't have the rear defroster but I do have the heated power mirrors and I have to push the defroster button on to heat my mirrors. Works great and it shuts off when the mirrors are toasty!

PS Also works great when driving thru Fog etc