Before i ask this, I know, most people unplug it or disable it.

Im choosing to fix it. A bird Got stuck in my upper shutter and now the actuator just opens and closes and clicks. The calibration stop for the open position is still there.

Here is my question, Does the actuator itself have the closed calibration position stop inside of it? I cannot find a closed position stop or anything that is broken on the shutter housing anywhere. I removed the actuator and it spins infinitely in both directions.

If the closed position stop is on the shutter where is it?

Thanks in advance.

 

Don't tell dealer how the damaged happened. Just tell him it's not working. You have warranty, use it.

 

Bumper to bumper went out at 36000, only have powertrain now.

 

According to my crash repair its only about $250 CDN and its not that hard to remove grill and replace.

 

Speculation, but it probably is a stepper motor driving it. Typically with these you simply observe the current at a given voltage to determine where the stops are. Much like how 3D printers can do sensorless homing, or how electronic throttles automatically recalibrate zero position.

 

The difference between a stepper motor and a servo is a servo has an encoder and knows position. A stepper just knows how many increments it has traveled. The system will count the steps for calibration and compare that to actual. The system will want to see X amount of steps traveled from open to close and have a tolerance. once its outside that tolerance it will trigger a fault code.

 

For anyone interested when the bird flew in the grille it stripped out the internals on the motor. I ordered another one off ebay and it worked fine.

For refrence my old motor would spin with almost no resistance. When it was in the shutter system it would open all the way then click for 30 seconds then close all the way and click for 30 seconds.

The new motor was much more stiff so that tells me the internals were gone in the other one. Stupid birds...

 

You are correct for throttles. I was thinking of idle air controllers which often use steppers instead of servos. Most electronic throttles are servos.

That said I wouldn't be surprised if the shutters are steppers given they don't need high speed adjustments. The downside is that the computer has to learn the stops every time it powers on, and they don't move quite as fast. Steppers are used elsewhere like in the HVAC air blend actuator.

Basically they calibrate by pushing into the stop, causing a spike in current which is picked up by the motor control sense circuit. Then the computer uses what is essentially dead reckoning to assume the position of the motor at any time by counting steps taken thereafter.

Sometimes a failure in the motor controller causes the sense circuit to malfunction and instead of just tapping the stop and moving back, the circuit keeps driving the stepper into the stop (because it can't sense the current properly) causing the characteristic CLACK-CLACK-CLACK noise for a few seconds after turning on as the motor winds up and slips repeatedly. Used to be a very common failure mode in blend door actuators.

In the event that there simply no longer was a stop to hit, I'd imagine they'd spin until a time limit was reached.