There is a fuse in the rear of the radio. Assuming that the thing does not power up at all, that is probably the problem. Remove ash tray insert, then 2 screws that were hidden, then the entire ash tray assembly comes out. Reach in and pull the radio straight out, you might have to pull down the 2 locking clips at the lower front of the radio. The fuse holder just pulls out of the radio.

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