Man I don't even know/remember what is my stock radio look like after having the supra for 10+ years. It was gone the next weekend after I bought the car. I didn't recalled reading about radio lock in the user manual.
Well, just pay the dealer to do it. BTW, they only unlock the unit if it serial number match with the VIN or you have to show them the received you bought the radio LEGALLY.
I had Honda reset the code on the HU on the Accord once. Because they're going to charge to reset even the car is under warranty, I just replace the radio fuse with a blow fuse and drive to the dealer playing dump that my radio doesn't work. They replace the fuse and reset the radio under warranty.
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