[SilverHyBu]

Thank you for the post showing the switch location, I had thought it was buried much further down than that.

Tired of the giggling, shaking and muttering, I pulled my console apart to have a go at fixing the problem.
I have a 2013 Malibu LTZ, here the switch is slightly different and in a different location too but still easily accessible.
I first tested the switch output (with a meter) by pressing the shifter lock lever. The switch toggled open/closed many times, then stayed open. I lifted the lever of the switch just a pinch and it closed. Could it be the switches are fine, it's the actuation of the switch causing the problem?

The bending trick on this assembly is a bit different. Simply pushing down on the lever will bend the lever at it's pivot point. This will not help the lever depress the plunger any further. The lever has to be bent between the lever tip and just before the switch plunger. This will have the lever pressing the plunger to near bottomed out. Hope this takes care of this botheration.

I can't find a way to post pictures of what I did, can someone guide me on how it's done on this forum?

Nice find.
Simple contact cleaner, ( most of which also has lubricating properties safe for switches) often solve problems like this. Sounds like you found a way to increase the spring pressure of the switch actuating system, which wasn't returning properly. If it happens again, I would disconnect it from power, (disconnect it) and shoot up the whole mechanism with contact cleaner.
I've repaired a lot of sticking switches and their activating systems like this.
That said, don't ever spray anything connected to power or any type of electrical system. Make sure it is disconnected physically (as in unplug the electrical connector) first to avoid any drama. Most propellants are flammable these days.

 

[SilverHyBu]

Sorry, that response went to the wrong person.

 

[SilverHyBu]

Very nice find and thanks for sharing it!
Your second video does show that when the actuating system returns as normal, the switch actuator arm fully engages the switch.
I think it's the actuator assembly, and not the switch itself sticking.
Seeing that, silicone spray might be helpful on the plastic shifter actuating system if it continues to give you grief.
Just an observation and suggestion in case bending the tab didn't make it work consistently.

 

[SilverHyBu]

I just did this fix last Friday. I maintain that the switch itself isn't the problem.
The shift mechanism sticks and doesn't trip the switch. It's not even the shifter itself, but the shift knob assembly. This is why you see some videos claiming that bending the switch trip arm is all you need to do. This is only successful because it allows the switch to trip even if the mechanism doesn't fully return. A little greaseless lubrication to remedy the sticking shifter knob is all that's really needed.
The plastic release button on the front of the shift knob is what needs to fully return to activate the switch.
When I installed the jumper, I also sprayed silicone spray on the plastic trip levers inside the shift knob as that is what sticks.
I believe this is why replacing the shifter itself doesn't fix the issue long term.
Installing the jumper allows the car to determine that it's in park using other parameters even if the switch doesn't make, so this fixes it even if the shift knob continues to stick.
Don't spray anything on the shift knob without removing it first since it does have switches inside for manual shift mode.

 

[SilverHyBu]

I went with rubber tube on the mechanism that presses the switch. I bought a switch but I don't seem to need it.

Yes, because the switch isn't the problem. The switch not tripping due to the shift mechanism hanging up is the issue in every video I've seen posted about this.

 

[SilverHyBu]

The problem with this issue is there seems to be multiple causes. A fix for one owner doesn't mean it is a fix for every owner. For example, for a long time GM's fix was a harness with a little jumper. It worked long term for almost no one - I think it worked for one owner on this forum. GM rescinded that bulletin and later included the jumper as part of a much more extensive repair process. On the Hybrid, "shift to park" can be triggered by a fault of the shifter just like any Malibu or by a catastrophic internal failure of the voltec unit. A couple forum members had to have the whole drive unit replaced and GM released a bulletin after numerous failures.

Have you made a guide or video showing how to implement your preferred fix?

I didn't make one but there are several videos showing the switch just not getting tripped like I experienced. I would expect the car to throw all sorts of codes when the park verification sequence gets interrupted. I wonder if some dealers were throwing parts at it based on all the codes. I do remember those threads.
So far, the fix is working for me.

 

[SilverHyBu]

Personally, I think the entire issue is just a sticking mechanism not triggering the switch. I fixed mine by removing the shift knob assembly, dousing the switch with contact cleaner (don't think the switch was the problem) and shooting up the moving parts in the shifter outer housing with silicone spray. I also installed the bypass/jumper harness at that time. If we do get the message (rarely), a flick of the shifter release button is all it takes. I believe the jumper allows the car to verify the park position even if it is out of sequence, so it's never caused a problem where we can't shut off or lock the car. Without the jumper, the car looked for verification of park in a specific order with the switch needing to be made first. If it got out of order, that's when it wouldn't let you do anything else, and I believe the jumper prevents that.