Slow power window problem

Question

On my 2000 Toyota Sienna, the driver's side power window behaves strangely. The window rolls down just fine. However, when closing it, it begins rolling up in the normal rate, but half-way up gets slower until completely stops. I then wait some time and able to continue the roll-up some more - and repeat this sequence until it is completely closed.

Basically, you can think of it as if I "charge" the window motor's very "small" battery, which depletes on the way up. Then repeatedly allow it to "re-charge" and get depleted again while gradually rolling up.

What is the cause of this behaviour?

What part do I need to replace/service?

Answer 1

Your window motor and/or regulator is going out. What happens is, the window motors have a thermal trip which tells them to stop when they get too hot. As a vehicle gets older, the window regulator and slides don't slide/move as well, so creates a lot more friction. The window motor starts wearing out because of this and more heat is produced, thus shutting down the motor. When it sits for a little while, the motor then cools down, thermal trips back to good, and you can then push the button and the window continues on its way.

Answer 2

What I've found in several of these is that the motor itself is fine, but it's internal thermal fuse goes bad (becomes higher resistance giving less voltage to the motor). I've even replaced the thermal fuse for a couple bucks and the motors then work like new. I wouldn't recommend doing this unless you are familiar with soldering and electronics.

Answer 3

I would like to take this time to share my thoughts in regard to the problem I've had with the 2000 Sienna.

I've resently changed the drivers side motor that had the same problem.

Only to have a problem a month later.

My problem was not my motor but instead it was due to the Increase friction.

Also the thermal fuse that is internal becomes very hot and it gets a higher resistance as well as giving less voltage to the motor.

This was causing the motor to turn off.

I found that my problem was that the tracks needed a really good cleaning.

It's probably a good idea to change the internal fuse.

But soldering is not my forte.

Answer 4

The power window motor is getting hot inside and shuts down. When it cools it starts to work. This is a sign that it is going bad. It is a good idea to replace the window regulator at the same time since the regulator will have to be removed to replace the power window motor. Also put extra grease on all moving parts.

Answer 5

The power window motor is getting hot inside and shuts down. When it cools it starts to work. This is a sign that it is going bad. It is a good idea to replace the window regulator at the same time since the regulator will have to be removed to replace the power window motor. Also put extra grease on all moving parts.

Answer 6

The purpose for the thermal protector is to provide a means to shut down the window motor in the event a child or even an adult has his hand in the open window while it is moving. These tiny protectors are located inside the motor and they sense the amperage going through them. When a motor binds slightly, the amperage rises sharply and this increase in amperage heats the thermal switch next to it and opens it. Out side temperature has very little effect on this since it is inside the motor and reacts quickly to a sharp rise in temperature.

Answer 7

To all who say the motor is getting hot;

When the wether is -30c, the window will only go down maybe a cm. When I park in garage car warms to +20c. The window now goes down fully and quickly when temperatures are 50 c degrees warmer.

How does the motor get "too hot" overnight in temps extremely cold but "cools down" when room temp or even extreme heat?

To me this discredits everyone's proposed solution. Without knlwing cars, it seems like a "pressure/vacuumed" related issue. A closed air system when cooled will decrease pressure. Also a colder material has less friction than the second material with exception of only water. Substances expand when heated and contract when cooled, thus surface area decreases when colder and thus friction is reduced. Again, this refutes suggestions of friction increase in colder temps.

Answer 8

I had a similar problem on a 2000 GMC Sierra passenger window. I cleaned the window tracks and then sprayed them liberally with arousal silicone lubricant. And in this case removed the window tint film as portions had been scraped off leaving a very rough surface that was causing much friction at the "squeegees" that clean the glass as the window travels down into the door. I bought a brand new regulator with motor for the driver side from eBay for $21. Couldn't believe it works great and while the motor was a bit smaller than oem, materials and build quality are decent.