1999 Riviera

[G-837077]

Trunk only will open with remote. Key will not turn and button on door is inoperable. It doesn't matter which position the switch in glove box is in. Check fuse and it's OK. There is another that appears to be a relay. Don't know how to check that

 

[DrivenDaily]

The relay is most likely controlled by the remote fob. It might also be controlled by the button on the door.

You will benefit from taking a peek at the wiring diagrams. You can download them for free here:

https://charm.li/Buick/

 

[LARRY70GS]

I'm surprised the key won't turn. I would open the trunk with the remote and then try and lubricate the lock cylinder and whatever else you can see. See if you can get the lock cylinder freed up.

If the trunk opens with the remote, then the solenoid is working.

Seems like you have 2 problems, the lock cylinder and the push button in the door panel, seemingly unrelated.

Remove the door panel switch and check it with an ohmmeter. Proceed from there.