I had a similar problem. The trunk latch on the way out, the micro switch wasn't closing and the trunk light was staying on. The design of the trunk latch is pony (plastic hook) - hence the "do not slam" warning tag. This may not be you problem but it's a good place to start.
There is a Cherry submicroswitch attached the the trunk latch. This switch controls the light and the instrument indicator. It also activates the alarm.
ks430 trunk latch
my trunk latch won't work what could be wrog
There is a handle behind the passenger seat. It operates a cable that connects to the trunk latch. Make sure it is not locked and pull it out. The trunk should open. If it won't pull out it is probably locked and will have to be unlocked first. Hope this helps.
Unplug the wires going to the trunk latch.
To fix a trunk latch that is stuck open, the teeth on the lock may have to be adjusted so the trunk will close. It is also possible that the cable for the trunk latch is broken. To fix the gas cap door latch may require a little bending and adjusting with a pair of pliers.
With a Large Hammer
It means that the car beieves that the boot/trunk is open. Either the switch is broken or the latch hasn't closed properly.
I would say that if you are having this problem most likely the latch has been slightly bent in or out, or the vehicle has been wrecked in the past. Also, the alignment of the trunk could be off. (wrecked) But a trunk latch can get damaged from slamming it over and over. Also, if it is a used car, you never know what has been done to the vehicle. Maybe someone locked their keys in the trunk and broke the latch in the past. Or, maybe someone broke into the car when it was previously owned and the latch has been replaced. You never know. People do strange things.
free
there is a cable that runs from the trunk release lever to the latch inside the trunk. you should be able to disconnect it from the latch inside the trunk