What's the cause of this trunk's sticky latch?

Dear Car Talk | Nov 01, 1995
Dear Tom and Ray:
Claire
RAY: It can only be one of three things, Claire; the switch itself, the wiring, or the latch inside the trunk.
TOM: Here's how you test it. Since your father sounds like a hot shot, have him show you how to remove the switch. Next time it fails, take off the two wires on the back of the switch and touch them together (that's what the switch does). If the trunk pops open, then you know the switch is faulty and replacing the switch will solve the problem.
RAY: If the trunk doesn't open, then the switch is fine and the problem is either in the wiring or the latch mechanism in the trunk.
TOM: So the next thing to do is see if current is getting to the latch. Your father probably has a little voltmeter or a test light. Again, when it's not working, have someone press the button and check to see if there is voltage getting to the wires at the base of the latch mechanism. If there is, try grounding the latch just to make sure it's not a grounding problem. And if that doesn't make it work, then you can conclude that the switch is good, the wiring is good, and the problem is definitely in the latch.
RAY: At that point, I'd try banging the latch with a hammer. Actually, if it were my car, I'd check for any obvious loose wires or connections in the latch that could be expanding in hot weather and shrinking back together when it's cold. If I didn't see anything, I'd check the price of a new latch mechanism.... and then probably resign myself to getting out and using the trunk key.
Claire
RAY: It can only be one of three things, Claire; the switch itself, the wiring, or the latch inside the trunk.
TOM: Here's how you test it. Since your father sounds like a hot shot, have him show you how to remove the switch. Next time it fails, take off the two wires on the back of the switch and touch them together (that's what the switch does). If the trunk pops open, then you know the switch is faulty and replacing the switch will solve the problem.
RAY: If the trunk doesn't open, then the switch is fine and the problem is either in the wiring or the latch mechanism in the trunk.
TOM: So the next thing to do is see if current is getting to the latch. Your father probably has a little voltmeter or a test light. Again, when it's not working, have someone press the button and check to see if there is voltage getting to the wires at the base of the latch mechanism. If there is, try grounding the latch just to make sure it's not a grounding problem. And if that doesn't make it work, then you can conclude that the switch is good, the wiring is good, and the problem is definitely in the latch.
RAY: At that point, I'd try banging the latch with a hammer. Actually, if it were my car, I'd check for any obvious loose wires or connections in the latch that could be expanding in hot weather and shrinking back together when it's cold. If I didn't see anything, I'd check the price of a new latch mechanism.... and then probably resign myself to getting out and using the trunk key.
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