I looked at the fuse schematic and I think there's only one fuse for both rearview mirrors so I didn't try replacing it because I thought that if the fuse was broken, then both mirrors would be not working. So what should I do?
My car has 144000 miles.
My car has an automatic transmission.
According to the wiring diagrams I have available to me, you are correct that both of the mirror heater assemblies are powered through a common fuse. I would suggest gaining access to the electrical connector on the passenger side mirror assembly and check the function. I would look to see if the black wire has ground, and the orange wire is getting voltage, when the switch is activated. If you are getting the correct voltage and ground signals, I would say that the heating element within the mirror has perished, and would need to be replaced. If this is something that you feel you could use a hand with, contact a certified mechanic, like those available at YourMechanic.com.
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