Trunk will only unlock with fob?

1999 BUICK RIVIERA
122,000 MILES • 3.8L • 6 CYL • 2WD • AUTOMATIC
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GLENNJL
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  • 1 POST
Trunk will only unlock with the fob. The trunk open buttons on door are inoperable, key goes in the cylinder on the trunk but will not turn. Tried the valet switch in the glove box in both positions, but the only way the trunk unlocks is with the fob. Checked fuse under seat. It's good. There is what appears to be a relay also, but don't have a way to check this.
Sep 30, 2024 at 3:24 PM
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STRAILER
  • ✓ASE Certified Mechanic
  • 54,832 POSTS
  • ASE Certified Mechanic
It does not make sense that the fob would be the only thing that opens the trunk unless the ground is bad for the trunk open switches. Here are the wiring diagrams so you can see how the system works (easy). The same relay is activated with the remote and it should not affect the key operation. I have marked the ground circuit, and I have included a guide to help with the test.

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

The key problem is a separate issue. Check out the images (below). Please let us know what happens.
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Oct 1, 2024 at 12:13 PM
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