Are you using the factory wiring harness? If so, there are 2 fuses. If not, it is easy and common to have the red + and black - wires in the wrong order. Really! Even after 20 years of working on them, it happens. Other than that, if you have another harness, or a couple of wires, hook them up when trying to program. Make certain the power supply can handle the amperage draw. I used a 5 amp power supply once, blew a fuse on the radio, then the power supply. Then I'd start looking at input diodes.
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Are you using the factory wiring harness? If so, there are 2 fuses. If not, it is easy and common to have the red + and black - wires in the wrong order. Really! Even after 20 years of working on them, it happens. Other than that, if you have another harness, or a couple of wires, hook them up when trying to program. Make certain the power supply can handle the amperage draw. I used a 5 amp power supply once, blew a fuse on the radio, then the power supply. Then I'd start looking at input diodes.