One touch down window does not work right, why?

[Silver99camry]

Hi,

I've had problems with my driver side power window not working properly some times. I've traced it down to one touch down function of the master switch. When I press the switch, I see +12 V at the motor terminals and window goes down. However, when it reaches down, I still see +12V for 3-4 seconds. After that, the thermal switch inside the motor kicks in and opens the circuit. Once that happens, I cannot use my window for about a minute. Once, the switch cools down, the motor is working fine again. If I do not use one touch down function, everything works like it should abd window goes up and down with no problems.

So, my question is, why one touch down function does not disengage when window reaches down position? Does anyone know how this function works? The manual suggests to check current in the circuit when the window goes down and when it reaches down. When window goes down it's supposed to be 7A, I get ~4A, when it reaches down it supposed to spike to >14.5A, I get 15A. However, it does not stay 15A for long, maybe for a second and the manual seems to suggest that it has to stay for 3-4 seconds.

So I have a dilemma here. Is this the switch not reacting to 15A what's causing my problem? Or, is it the motor not providing enough current for long enough to trigger the switch. It would help if I knew exactly how one touch down works and what disables it. Anyone?

Thanks

[cykaaro]

I honestly don't know about the in's and out's of it, but what makes me say 'hmmmmmm' is when you say your switch needs to cool down. Am I right in taking it that your switch actually gets hot? If I put mine down, and even hold the switch down, I can turn around and just put it up without issue, but the switch doesn't heat up at all. If it is heating up, maybe there's something amiss with the switch.

[Silver99camry]

I was talking about the thermal resistor inside motor assembly. It's designed to get hot and break the circuit if hight current flows through for more than 4 seconds. it's in the manual. It protects the motor from burning. During normal operation though it should never get to this, auto down should disengage before the the resistor inside the motor opens up.

It's a good idea though, I'll check if my master switch heats up.

Thanks

[Kep]

I can't say how the switch works but here is a photo:



The two yellow lines on each side point to the up and down contacts that close when you activate the one touch feature. I believe these heat up when the window closes and they pop open. The blue line points to where the rocker finger switch conects. That in turn pushes the metal rams to close the contacts.

It might help if you get in and clean the contacts. Easy to say, a pain to do. Check out the DIY section:

DIY: Power Window Master Switch

and grandaCoder’s recent post:

My Power Window Struggle / 1993 93 Camry

These may help.

Kep

[Silver99camry]

Thanks for the picture, it helps. I stopped by my local junk yard today and they let me try 2 other master switches for my car. Both of them showed the same problem as the original switch, one touch down not disengaging. Based on your picture, I think it is not a switch problem in my case. It looks like that in order to disengage, auto down contacts need to heat up. I think my motor does not provide enough current when it stops. According to the manual the current has to be 15A when it stops for at least 4 seconds. I only get 15A for a second or so, then the thermal resistor inside the motor disconnects. I think thermal resistor might be out of specs. Unfortunately, it's part of the motor and it has to be replaced as one unit.

I've tried 3 different switches so far and the problem is still there, so I think it's safe to assume it is not the switch. I am going to try swapping the motor next.

Thanks

PS.

I am also considering disabling one touch down feature all together. it'll be cheaper than replacing the motor. I think all i have to do is to not allow contacts in your picture to touch.

[Kep]

Other than the time to disassemble & reassemble the switch I can't see where it would hurt to put a piece of tape or something between the contacts. Might disable the one touch. Maybe the junk yard has a motor that they'd trade for the master switch. If not, let me know. If you're willing to wait until I mail it I have an old motor that I'd sell you. I think that I know where I put it.

Interesting idea about the motor needing to be able to put out current long enough for the switch to work. I hadn't thought of that...

Luck,
Kep

[Silver99camry]

Originally Posted by Kep

Other than the time to disassemble & reassemble the switch I can't see where it would hurt to put a piece of tape or something between the contacts. Might disable the one touch. Maybe the junk yard has a motor that they'd trade for the master switch. If not, let me know. If you're willing to wait until I mail it I have an old motor that I'd sell you. I think that I know where I put it.

Interesting idea about the motor needing to be able to put out current long enough for the switch to work. I hadn't thought of that...

Luck,
Kep

How much do you want for the motor? My car is 99 Camry, will your motor work? What was the reason for you replacing it?

I found this test in the manual for the one touch down function. It says that on the way down motor current has to be 7A and when it reaches down > 14.5A. That's what makes me to believe that the extra current is used to heat up the contacts and break the connection. However, if connection is still there after 4-60 seconds, then thermal breaker inside the motor is supposed to kick in and break the connection. I think in my case thermal breaker kicks in too early. I have to wait 60 seconds before motor starts working again.

Thanks

[Kep]

Oops, messed up again, I thought you had a 3sfe. Don't know why. No, I doubt if it would work. The 3sfe was a gear and arm regulator. The 5sfe uses a cable regulator. I would be surprised if it had the same gear/drive on the motor axle and after 9 years the electric connection is probably different. Sorry.

Here's the motor:








Kep

[cykaaro]

This is what the '97-'01 looks like.



and this is supposedly the motor:

[Silver99camry]

Could work I guess. Advance AUto parts list the same part number for Camry 87-91 and 97-2001. Mine has no cables.
Thanks

PS. Opened my master switch today and it looks nothing like yours. No loose parts at all. Just bunch of relays and switches. You cannot even clean it.

[Kep]

I can't say. The photos are remarkably similar. If the part numbers are the same that is reassuring. However, It sounds like the switch circuitry is relying on resistance feedback from the motor. I can't say if the vintage motors would provide the same "information" as the new ones or not.

Kep

[Silver99camry]

Well,
I just went ahead and disabled one touch down function. Will see how that works out. W/o one touch, window goes up and down multiple times just fine.

Thanks