How to test a trunk locking device?

2005 Mazda 6 - 133,000 miles. Can anyone walk with me through the trunk test drive release steps? My wife’s tree trunk stopped open when using the remote control or pressed the release button on the control panel. The trunk opens when using the key. I’m trying to determine whether the problem is actuators or something in the wiring. I own a digital multimeter, but my electrical knowledge is quite small. For the most part I have used it is to test the battery capacity and voltage under load. I appreciate any guidance that anyone can provide.

From what I can tell, the trunk latch system is powered through a 7.5 amp trunk fuse, so check that. From there power goes to the truck lid opening relay. The relay is controlled by the door lock control module, the truck lid cancel switch and the trunk lid opener switch. When the relay coil is energized, that connects contacts inside the relay that allows power to pass to the trunk lid lock actuator. Where I’d start if I had that problem is to use a volt meter to determine if the lock actuator was getting power or not, when it should be.

It appears to me that when both the trunk lid cancel switch and the trunk lid opener switch are closed, the relay will actuate. Or if the trunk lid cancel switch is closed, AND the door lock control module provides a ground, that should also actuate the relay.

trunk lid relay: engine compartment
trunk lid opening switch: under dashboard, left side
trunk lid cancel switch: under dashboard, right side
lock actuator: near trunk lock

Go here to see what appears to be your original inquiry- How to test a trunk lock actuator?