My inside trunk release button suddenly would not open the trunk. My key FOB would not release the trunk either. I took the valet key and manually opened the trunk. When I went to close the trunk back, the pushbutton closure on the trunk lid would not engage the automatic closure mechanism either. I manually closed the trunk and all fits well.

I checked the valet lockout switch in the glove box and it was not engaged.

I changed the batteries in the FOB per my Dealer's suggestion and that did nothing to relieve the problem either.

How can I fix the automatic function so that the trunk can be opened either by the key FOB or the trunk release on the dashboard?

 

You motor could be shot, not a cheap one. I know on my old LS430 the trunk release died and the cheapest I could find a replacement part was around $600, even eBay prices were over $350 for used ones.

Try for giggles to pull the battery for about 2-3 min and plug it back in, that will "re-boot" the car and might bring it back.

 

I had that problem with my 460 and it cost about a grand but covered under warranty.

 

Operation of the disable switch can be confusing sometimes. Here's a clip from the owner's manual, just in case.

 

FWIW, there's plenty of LS460 units on Ebay for 200-250 dollars. Here's one: http://www.ebay.com/itm/13-14-15-16-...BY2VJe&vxp=mtr

 

I wonder if the 2007 uses the same part?

 

Nope, But they're about the same price for 07-09 : http://www.ebay.com/itm/OEM-2007-200...dYyGZR&vxp=mtr

 

The lock mechanism recommended may in fact also be a problem, but how would that account for the trunk not closing when the closure mechanism button is depressed?

 

When I was having problems with my trunk the metal key inside the key fob was the only way to open the trunk. The inside release button, outside release button and key fob button did nothing. The self closing only made a grinding noise and wouldn't close when depressed,

 

Sounds like the problem I had which was a bad latch. Disconnect the ground for 30 seconds and try to open the trunk with either the fob, or the button on the dash.

 

Did you get the trunk release fixed? I just bought a Ls460 and the trunk won't open with the remote, or trunk button. The valet switch is off. When I hit the trunk close button after I manually open it I hear a ticking sound like a bad relay or something. Is that the symptom of a bad motor? I hope the small dealership I bought it from will cover it.