Did anyone check to see if the trunk latch switch is bad? Makes more sense than a "blown diode"

 

The blown diode causes the trunk light to always be on

 

As previously suggested, you can put an on/off switch inline or utilize a mercury switch that goes on and off when the trunk lid is raised or lowered.

 

Honestly, I'd put your stock incandescent bulbs back in and take it to a different dealership. If you installed them with power going to the circuit, you may have bridged the circuit, which could cause damage to the BCM.

An important tip, make sure the socket you are swapping isn't active when installing new bulbs. Though it's extremely rare, "Hot plugging" can cause issues to occur.
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Sounds to me like that dealership is trying to take advantage of you though. $3,000 is ridiculous, even if they have to replace your entire BCM (unlikely). It probably is just a simple fuse.
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Nick C.

 

I m sure power was on the circuit when I replaced them. The only trouble I had was with the trunk. Every time I changed the light the fuse blew. It's all been very strange. The only thing I worry about is if something electric goes wrong the dealer might give me a hard time. Even if I go to another dealership I'm sure it's in the system?


That at being said, I have put a battery led light in and all is good. Now the other day I open the trunk and the trunk light comes on. I check and it's goes off like it's supposed to. So somehow it fixed itself. Lol

 

Lol, well, that's good!

If the service department tells you that the LEDs "draw too much power", grab your keys and leave ASAP lol.

Nick C.

 

Well, a happy ending after all... Good for you!