Cruize trunk keeps popping open

[DrPizza]

Anyone have a clue what causes this, or rather, how I can fix it? Chevy Cruize, 2012. No key for the trunk, just the button on the key fob. First thought was it was the key fob. Took the battery out. But the locking mechanism at the trunk opens it about every 5 to 25 seconds. Ahhhh, where's the spare key. Battery out of both. Problem continues. Maybe there's a capacitor inside holding a bit of a charge - wrapped them both in aluminum foil as a faraday cage. Well, that eliminates the key fobs.

Disconnected the battery from the car for 2 minutes; reconnected it. Immediately heard the click/pop sound of the mechanism opening. Then opening again in 10 seconds. And again and again. Located the fuse that says "trunk lat" Pulled the 10A fuse. <click/pop> What the heck?! Removed the whole fuse system so I could get to the trunk relay, pulled the relay. The familiar at this point click went away.

BUT, although this keeps the trunk closed, and thus secure, it's now impossible to get into the trunk. Anyone have any ideas?

 

[C1]

There is an updated component you must switch out.

On page 5 of this document it addresses the issue, New 2X Trunk Release Relay

http://sandyblogs.com/techlink/wp-content/uploads/2013/05/May-Techlink-2013-F.pdf

 

[boomerang]

There is an updated component you must switch out.

On page 5 of this document it addresses the issue, New 2X Trunk Release Relay

http://sandyblogs.com/techlink/wp-content/uploads/2013/05/May-Techlink-2013-F.pdf

That appears to be a correction for the inadvertent press of the button on the fob which DrPizza has eliminated as the source. The replacement relay as you stated will require a double press to pop the trunk.

It could be a short in the wiring, a bad switch, a funky relay or the BCM. There may be multiple switches. A button somewhere in the interior and possibly a touch pad back under the lip of the decklid. I don't know if the Cruze has that feature but there most certainly will be a button or buttons somewhere in the interior.

See if there is another identical relay you could swap in briefly. If that doesn't correct it, I would then access any switches and disconnect the connector. Obviously you'd want to do this one at a time. I would then disconnect the connector at the decklid release and with a DVOM see if there is current flowing to it. At that point you're down to wiring (a short) or the BCM. Fortunately it happens instantly so you'll know right away. It would be a pain if it was an intermittent thing that happened only once in a while.

The .pdf C1 linked to has a wiring diagram but understand that it is generic and not specific to your Cruze.

 

[DrPizza]

Thanks guys. Turns out it was the tiny touchpad at the trunk. I'm going to assume the salt from NY's roads somehow made it inside that pad/switch. The only corrosion on the entire vehicle is, apparently, something inside that switch, and the screws holding the license plate light covers on (adjacent to that switch.) I simply removed all the little plastic grommets, (slide a flathead screwdriver in the slot, and pop the center part up, then use the screwdriver to pop the rest of it out), a couple screws for the inside closing handle (7mm), and popped off the plastic protector on the actual latch mechanism, and removed the inside panel of the trunk lid. I then reached up inside and pinched the wire harness connector thing so I could pull it free and disconnect the wire to that touchpad switch. Then, put everything back together. My wife can no longer open it from the outside, except by pushing the button on the key - but that's how she does it anyway, since in the winter, that part is invariably dirty from slush on the road. Eventually, I may stop by the dealer and check on the price of a replacement part. To get to it, there are only 4 more nuts that I'd have to remove from inside.

I detailed this, in case someone else finds this thread, like I had found dozens of other articles, but none which actually had my problem. I'm not sure, but from what I understand of the circuit, the GM bulletin fix would have also fixed this problem, despite an incorrect diagnosis that they're assuming it's because someone's accidentally touching the button in their pocket - that was the first place I assumed the problem was, hence removing the batteries and isolating the key fobs. But, there were dozens of people claiming, "no I wasn't! Both keys were sitting on the table." "Well, your button must have been stuck down or something." Replacing the relay and eliminating the symptom would be a 1 minute job though, instead of 15 minutes to fix the cause of the problem; so maybe it's intentional. I wonder how the switch cost compares to the relay cost (Chevy Malibu forum listed the fix at $78.)

 

[NutBucket]

Nice. Glad you were able to fix it.