Hi my name is John.
Disconnect the C3 CCN connector and apply 12 volts to cavity 24. If it unlocks replace the CCN after inspecting the CCN connector for spread, damaged or pushed out terminals. If it still doesn't unlock disconnect C201 and apply 12 volts to the TN/YL wire in cavity 15. If the latch opens repair the wire between the CCN and C201. Next remove the rear seat and open the decklid manually. Apply 12 volts to the TN/YL wire at the latch. If it opens repair the wire between C201 and the latch. If it doesn't open, add an additional ground wire to cavity 1 of the latch connector and apply 12 volts to the TN/YL. If it opens repair ground circuit. If is doesn't open replace the latch assembly.
Disconnect the cluster c1 connector, deck lid latch connector and trunk light. Load test the g78 circuit by supplying fused power to pin 23 of the ccn's c1 connector. Ground the g78 at the decklid switch and trunk/cargo lamp pin 1 through a head light bulb. If the bulb is dim or does not light at one or both of the connectors- there is either an open, wire damage or high resistance in the g78. In the case used to create this file it was found s301 had broken strands of wire- thus not able to carry the amperage load needed to supply a good ground for the lamp or decklid switch
Let me know what else you need.
YES IT IS.