Piston Slap: Locked in the ‘Rolla, Seeking Exploratory Surgery

James writes:

I have a 2010 Toyota Corolla, and one of the people that rode on my back seat turned on the child safety lock on the back passenger side door. My car is a base model, no power locks or power windows.

I went to open the back door, and I can hear it sliding in the door but it will not open. I have worked on cars every since I was 10 (I’m 52 now) and everyone I ask at a shop tells me that I will need to replace the whole door latch on it. But I cannot open the door to do it without damaging the door. What can I do to fix it?

Sajeev answers:

James, this can be a dicey process, but let’s go through the steps and hope they apply to your Corolla. But for those who may not know how a child lock feature works, let’s step back a moment and see the system in action. In theory, the exterior door handle is supposed to always work, no matter the position of the child safety lock. But we know how great theories are, in general.

Okay, we are now all on the same page. Since these systems can fail, they require addressing the issue without the benefit of an open door. The first step is to see how the door panel is removed in normal circumstances. Luckily rear door panels are far less complicated then the front doors (provided we aren’t talking about something like a Maybach).

As we see in the video above, there are two places where attachment hardware has to be removed from the door panel. Mercifully, both the armrest and the interior door handle cubby are easily accessible with the door closed. Since you do not have power windows, you will also remove the window crank at this point.

The final step entails pulling off the retaining clips that encircle the door panel. This is where things get challenging, because you must get creative. You will either partially or fully remove the rear seat to get a pry tool between the metal door and the plastic door panel. (And you might need a removal tool with a long handle.)

Most (all?) Corollas have a fold down rear seat, suggesting you need to remove the filler panel that’s between the rear seat back (that part that folds down) and the side of the car’s body. The video above is for a Ford Focus, so the steps get vague from here: Sometimes you remove the seat bottom and the seat back to access the lower corner of the door panel. You want the least amount of obstructions going forward, so removing more trim in that area isn’t necessarily a bad thing.

Just like you saw in the second video at the 1:14 mark, I would pull the first retaining clip by grabbing on the panel’s lower cubby toward the front of the vehicle. (The other end of this panel is problematic, as it has a lip that extends into the body to meet the door’s rubber seal.) Free as many clips as you can from the front half of the door panel, then use that long handled pry tool to reach the clips that are hard/impossible to reach on the back half.

Judging by this video, you might need to pop that first retaining clip, and the rest will fall like a house of cards. Or perhaps that’s just be being an optimist. This task certainly will be a challenge, but I believe you can get it done pretty easily once the rear seat is out of the way.