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How to fix a Toyota Corolla trunk latch release cable
Many cars have a mechanical cable going from a little lever on the driver side to the trunk
and it allows you to open the trunk. The Toyota Corolla 2009 requires the lever to be pulled quite
far up and this bends the mechanical steel cable significantly. It will eventually break.
To replace the entire cable assembly is quite expensive because it's difficult to remove
all the covers and carpet pieces to do the replacement. Here is a much easier method which involves
pulling the old steel cable out (not the sleeve), reversing it and extending it with an shift cable from a bicycle.
The total cost in materials is only a few dollar and you can do that at home. No garage visit needed.
You can watch this youtube video to understand how to get to the lever near the driver seat
and how to open the cover in the trunk. You don't need to watch the entire video:
Here is what it looks like when the cable is broken. There a lot of space in the trunk area behind
the number plate. We will build a little gadget to extend the broken cable to go into the space behind the number plate.
There would not be enough space to do this in the front of the car.
Front lever with broken steel cable
Trunk side view of the opening mechanism, cable already pulled out a bit.
The trunk side part of the cable is terminated by a little aluminum ball where as the front end
of the cable requires a cylinder shaped termination to hook into the lever. It's possible to file
the ball down to a cylinder shape that will fit into the front lever.
Here is what you need to do:
- Pull out the old cable
- File down the big aluminum ball termination to a rounded cylinder shape such that it will
hook into the front lever
- The steel cable is a 1mm cable galvanized with zinc. Take a soldering iron and tin the cable
near the broken end. Do a clean cut and sand down the tin such that there is no bump. The tinned cable end will prevent the cable from frailing while you push it back into the sleeve.
- Cut the steel sleeve of the cable in the trunk somewhere behind the number plate.
- Build the little gadget shown below which will allow you to extend the cable with
some electrical wire clamp terminals.
- Buy a bicycle shift cable (break cable is too thick). Bicycle shift cables have a very
small aluminum cylinder at the end and you will have to add a few small washers to prevent
the cylinder from slipping through the hole for the pull mechanism in the trunk.
To extend the broken cable with the bicycle shift cable we build the following
little gadget. It has two small wood blocks with 4.5mm holes going half way into
the wood. A 2mm hole continues to the older end of the wood block. This is inserted
into the cable assembly. It makes a mechanical connection between the plastic coated
outer steel sleeve while allowing us the connect the inner steel cable with some clamps.
I used clamp terminals for electrical wires but any type of clamp mechanism for
steel cables will work.
The little gadget to interconnect two steel cables. The steel wires are clamped together in the open area between the wood blocks. The gadget is about 15cm long.
The clamp terminals for electrical wires which I used look like shown in the photo below.
Any other clamping mechanism for steel cables will also work. I removed
the outer plastic insulation because it's not needed for this application.
I did unfortunately not take any picture showing how I clamped the steel cables (the old
and reversed trunk latch cable and the bicycle shift cable) together but it's quite simple
you just insert both steel cables into the clamp and then you tighten the screws. The little gadget
shown further up allows the clamp to move in the space between the wood blocks when the cable
is pulled. The little gadget just keeps the outer sleeves apart and transfers the mechanical forces between the sleeves.
The cell phone network was heavily congested but it worked well off hours (early morning, lunch time and late evening). It
This is what the final assembly in the trunk area looks like. I have wrapped white plastic foam
around the interconnect gadget to prevent it from making any noises when the car drives on
an uneven road.
Repaired Toyota Corolla trunk latch release cable, view of the trunk area
The reversed cable in the front before it was pushed into the sleeve. This used to be the round aluminum ball termination in the trunk. The aluminum ball has been filed down to hook into the lever mechanism
© 2004-2024 Guido Socher