I have a problem with the trunk lock in my 2002 S60. When closed, neither the key fob nor the button in the lid will unlatch the trunk. I opened the trunk with the key and in troubleshooting the lock mechanism found that the mechanism will work (using either the key fob or the release button) if the trunk lid open more thak 45 degrees, but will not work if it is open less than 45 degrees. If the lid is less than 45 degrees, I can hear a relay click, but the mechanism does not unlock. Raise the lid a few degrees, and it unlocks. I have taken the lock mechanism out of it's mounting on the trunk lid and it works in any position, again as long as the trunk lid is open more than 45 degrees. Is there a position sensor in the circuit anywhere? I can't seem to find anything, and the wiring harness appears to be in good condition.

 

Were you able to solve this problem? I have the same issue, getting sick of using key every time i need to open the trunk.

 

Same problem here with my 2004 S60. I even tried a UEM reset and that didn't fix it. There must be some kind of sensor measuring what angle the trunk lid is at that's going bad.

 

I have a similar problem. I think the answer is the wiring harness. I did not have any visual damage or even deformation on the harness insulation. However, when I cut open the insulation, I had clear damage to to wires. I am currently looking for the harness. But I would think it would be the least expensive way to start troubleshooting

 

Sorry, I have a 2002 s60.

 

this may be a dumb question, but my 04 s60 2.5t has a "lockout" button- sorta like a valet button that keeps everything but the key from unlocking the trunk. has anyone check this? mine is under the radio cluster just above the pen holder. if the button has not been pressed, maybe it is a malfunction in this circuit?

 

I have a 2001 S80 that had the same problem... neither the key fob nor the trunk button worked but I could hear the relay click. I disconnected the trunk lid wiring harness at both the trunk lid solenoid and inside the trunk on the left near the CD changer. After that it was easy to detect an intermittent short in the wiring. Slicing the cable sheath open at the point where the cable entered the trunk LID, most every wire in the cable at that point had its insulation damaged, some showing an inch of bare wire. I re-insulated all with electrical tape and fixed the problem. Note that the fuse may have been blown too (mine was). Now I need to find a new wiring harness so I can complete the job cleanly. A Volvo mechanic told me sometimes the problem is the solenoid itself, so check the resistance across the solenoid terminals with an ohmmeter to be sure. I believe mine registered 80 ohms which indicated to me that the solenoid was not the problem.

 

Did you ever figure this out? I am having the same issues with my trunk.

 

We have a 2002 s40 having this issue. We always park in secure areas so don't need to lock the doors which might help us out in the long run, but .... We seem to have solved this for our purposes. We lubed the latch mechanism and the cylinder face plate. The cylinder face plate got stuck half-way in. Then we noticed there is a thin black rubber gasket that goes around the edge of the black cylinder face plate on the trunk lid that was sliced in two and coming out. It prevented the cylinder from moving freely. We poked it back around the edges of the faceplate which began moving again. We could hear the trunk lock responding to the remote, but still wasn't opening. Climbed in through the back seat and released the trunk lid using the emergency release and it was able to be lifted, though it didn't pop open. We locked the trunk lid with the key, unlocked and it clicked and worked. The more we tried, the more that gasket worked its way out again, so we removed it as it seemed to continually cause the cylinder to bind. The lid got stuck again, so once again we pulled the emergency release, and now the lid opens normally when depressing the cylinder and lifting the lid.