I have a 2008 XJ and read all the threads about fixing the speakers. I have the same problem with all 4 not working. Took the drivers side off and sure enough one side of the voice coil wire had no continuity.
Fixed that and plugged speaker in but still no sound. Took it back out and measured between the terminals and got nothing? It's an open.

Went to the back door and same thing but before I soldered it I measured the voice coil directly and again it was open?
Do I have that many bad speakers? I might as I found the drivers front dash speaker not working too.

I got the last door speaker out and it also needed the jumper wire fix but I had continuity on the voice coil!
About 2.5 - 3 ohms. Made the repair and the speaker works. So Looking for 3 replacements and found several on EBay.
Just need to make sure they are good.
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