My trunk won't close automatically like it used to. Also, my third brake light is out and the trunk interior lights no longer work.
It sounds like you might be having a wiring issue. Most of the wires that go to the trunk are wrapped up in a wiring harness. The harness is routed in from outside then splits up and goes to its respective receiver. If the harness gets pinched or cut somehow, the circuits that it supplies will stop working. In your case, the third brake light, trunk motor, and trunk light. Finding electrical problems can be troublesome. I suggest seeking help from a qualified mechanic, such as one from YourMechanic, to help you solve your trunk problem.
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