Yaris HB 2008: Cannot open back door, lock/cylinder move, but cannot release latch

[eepp]

Hey thanks 06YarisRS!

You're giving me some hope here.

As I wrote, if it's definitely broken, I don't care if I can buy a cylinder without its key... I'll just use the electric actuator to lock and unlock the back door.

I'll look into it, but how does this work exactly? I'm thinking this part with the cylinder (see photo) is linked to the latch with a cable? Or is it directly coupled and there are cables to the actuator?

I will follow your directions anyway. Do you know if the parts are the same for the 2-door and 4-door HB?

[06YarisRS]

Originally Posted by eepp

Hey thanks 06YarisRS!

You're giving me some hope here.

As I wrote, if it's definitely broken, I don't care if I can buy a cylinder without its key... I'll just use the electric actuator to lock and unlock the back door.

I'll look into it, but how does this work exactly? I'm thinking this part with the cylinder (see photo) is linked to the latch with a cable? Or is it directly coupled and there are cables to the actuator?

I will follow your directions anyway. Do you know if the parts are the same for the 2-door and 4-door HB?

Happy to help. The button to latch mechanism itself has no cables. To be honest, I rarely lock the hatch and not even sure if my power lock button will control the hatch lock. It does have an actuator that is connected with a nylon mechanism. I will go test shortly to see if the door actuator will lock and unlock the hatch.

I expect that it's the same mechanism in both 2 and 4 door.

Here is a pic from when I fixed my 06 latch with some additions to help you understand how the mechanism works.



It's really quite an ingenious bit of engineering, but it's really prone to contamination and seizing, hence the need to regularly blast it out with a cleaner and then lubricate.

I wish now that I'd taken pictures yesterday to help illustrate for you the workings of the whole mechanism.

[eepp]

Thank you for the information again, it helped a lot.

I'm documenting the process here with more photos.

The little lever attached to the key cylinder that releases the latch mechanism on the car can skip out of position to the wrong side of the latch arm.

This is indeed what happened, I guess when I hit the whole cylinder when it was frozen with a 2x4 stud.

When you remove the little rectangle cover on the back door's trim, it is quite straightforward and easy to open the back door. I guess this is the exact purpose of this little opening.

When the back door is opened, this image from another thread helped:

reardoor1.jpg

Start by removing the claw which is close to the latch. You need to pry the trim a little bit and press on the claw with a flat screwdriver to release the trim. Then work your way around with a big flat screwdriver and a flashlight, and make sure to always insert the flat head between the white plastic clip and the black trim, otherwise the clip "socket" on the trim could break. This happened to me, but only once! I don't understand why this trim needs three claws and nine clips...

This is the claw near the latch:

IMG_1203.JPG

This is a white clip:

IMG_1204.JPG

This is another "claw" (the other, white part stayed on the door's steel frame). Those claws are on the two corners near the car (opposite side of the latch). Make sure not to lose the white parts:

IMG_1205.JPG

This is the whole removed trim (back view) with my dirty X230:

IMG_1202.JPG

This is the latch (left), lock assembly (top, I don't really know the real name of this whole part), and actuator (bottom right):

IMG_1207.JPG

This is the (first) issue:

messiness810.jpg

The red part (on the lock assembly) should be above the yellow part (latch assembly) to press on it. When you press on the cylinder, the red part pressed on the yellow part. What decides if, when you press, the latch unlocks or not is the white part on the lock assembly and this is set by either the key or the actuator. There's a video below which shows how this works exactly.

Now it's okay:

IMG_1208.JPG

This is the latch assembly with the three 10 mm bolts removed:

IMG_1206.JPG

This is the lock assembly when the latch is removed:

IMG_1209.JPG

Remove that 10 mm bolt and turn the whole assembly to remove it from the knob which still holds it, then you get:

IMG_1210.JPG

That lock assembly was very dirty. I used brake cleaner and then a dry lubricant (which is rated for -65°C and one of the use cases is to lubricate a lock), always turning the key in the cylinder a lot to clean it as much as possible.

I don't have any photo of the assembly before cleaning as I was too excited to clean it, but for the purpose of this documentation, it doesn't matter. Here are the three parts, somewhat cleaned, of the lock assembly:

IMG_1211.JPG
IMG_1212.JPG

Here's a video showing how the lock assembly works. The white part I turn with my fingers, again, is controlled by the key or by the actuator so that both methods can lock and unlock the back door. It is indeed a nice piece of engineering. In my case, this cylinder was frozen and dirty, so it would not come back, even though there's a huge spring to push it back.

https://www.youtube.com/watch?v=TC1VRUgCXrs

Everything works fine and is smooth now!