Before I tear into my car trying to pinpoint the issue, I thought I'd throw it out here to see if anyone else has experienced something similar. When I press the tonneau release switch it seems like the passenger side releases, but the driver's side doesn't. It was working about 6 months ago, and it still does work on rare occasions. It seems like this is an issue with the tonneau release solenoid itself. What do you guys think? Since I know it's a common issue with these cars I will note that the trunk switch and trunk pulldown motor are both working properly.

 

I know sometimes I have to pull up gently on the tonneau for mine to sometimes open. I figure there are 3 possibilities. Since your button works on one side:
1) You might have a bad solenoid,
2) bad connection, might be as simple as something unplugged or corrosion on the plug. or a broken wire... Test the wires from side to side.
3) just out of adjustment.

John

 

You haven't told us if you hear both solenoids firing when you press the tonneau release switch. If it is firing, then there are two things I would try. First check that the latch is not gummed up and is still able to release easily. If not, remove the latch and soak it in WD40, then blow off with compressed air. Lube with graphite dry lube. If it is not gummed up with dirt and old grease/lube, then the tonneau J-hook may have gone out of adjustment due to the body bending a bit with age. It is fairly simple to determine this. Go onto the side that is failing to release on the first pop. Reach into the opened door and press the tonneau release switch. If it doesn't release on the first pop, then gently press on the tonneau and see if it releases now. BINGO! you just need to add some shim spacers to move the J-hook down slightly so it is properly centered in the latch. Unbolt the J-hook and copy one of the existing shims (if they were used) and make some more shims. I use .020" thick aluminum for some other items I make and always have plenty on hand to make things such as this. It is also handy to reinforce the back-side of plastic trim pieces that crack and repair them with epoxy.

Lon