L_perm

When opening my sunroof using the one-touch function, the motor continues to run for 3 or 4 seconds after the roof is fully open, as if some actuator that shuts off the motor is not working properly. It kinda sounds like it grinds down to a halt.

Is there an adjustment of some kind that I need to make to a motor shutoff switch of some kind? Or, is this normal?

Thanks,
Louis

MainePorsche

Are you sure your switch isn't sticking ? I do not recall our factory switches having a one touch function.

Mrmerlin

its a normal function^^^^,
the motor controller senses the higher load on the motor,
and then shuts it off .
NOTE since Porsche did not use limit switches like the 944 uses.

MainePorsche

Thanks Stan.
The load sensing by the motor I've experienced, but I was posing a question to Louis regarding his perception of one touch switch activation. That wouldn't be right.

MjRocket

He probably has the newer style hans/champagne switches wich have this function via a DEI relay module

Calgary Ole

One touch switch is standard from 90 onward I believe. My 1990 is 'on touch' or 'express'

MjRocket

I was not aware of that, gladly learning something new every day!

MainePorsche

Thanks, I didn't know MY 90 and up had this. Now I do.
I'm one of those old analog guys.

L_perm

Not a sticky switch. Works just like the window switches--one touch down, one touch open. I wouldn't buy one of those cars they had in the old days that made you hold your finger on the button. I've heard stories about those good lo' days when you had to actually open sunroofs with extended finger pressure. Sounds horrible.

So Stan, is that 3 seconds of extra motor time about right? The motor will start to slow when it encounters the friction and slowly "grinds" to a halt, for lack of better term. There is no real grinding, but it just seems like it would be hard on the motor, or the cable, or something.

Thanks,
Louis

Calgary Ole

Could be as simple as replacing a relay to the newer style?

I don't remember my motor staying on a few seconds but I'll go out and check

Mrmerlin

the clutch in the transmission may be worn and thus its slipping so the motor is running longer

L_perm

This is the first thing that occurred to me, but I wasn't sure the mechanism worked that way. I'm almost sure this is the issue now that you've confirmed my initial intuition.

Is the clutch serviceable/replaceable, or do you just have to replace the whole tranny-motor mechanism?

Thanks again.

Calgary Ole

Ran out to check. My motor shuts off pretty much immediately.

L_perm

Good to know. Thanks for checking.

Alan

Yes exactly this - a stronger clutch will cause a faster stop - because the motor controller will see a bigger current spike when it stalls.

Alan