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BMW N20 electronic wastegate

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I would like to use a Link G4+ Force GDI to run a BMW N20/N26 engine.  The later N20s and all N26s use an electronic wastegate actuator.  This is similar to the one in another thread, but since I have specific details to the one in my car I decided to start a new thread.

First what I measured:  It has a 5-pin connector, with a built in position sensor (using 3 pins - power, signal, ground), and a brushed DC motor (using 2 pins).  If I apply voltage one way to the motor, the actuator moves.  If I remove the voltage, it stays in position (i.e. there's no return spring).  If I reverse the voltage, it moves back.  Again when I remove the voltage, it stays in position.  I measured the resistance of the motor, and it's 4 ohm.  I measured more than 2A when driving it using a dying 12V battery (~10.4V).

I see two problems with this:

1. It is more power than the any of the Force outputs can handle, barring the e-throttle drivers (which I need for the e-throttle)

2. It requires a full h-bridge output, not a single output pwm.

Am I right that G4+ Force cannot handle this?  I am considering building a simple wastegate controller that translates PWM duty cycle of the Boost Control output to a position, and drives the actuator based on that.  I already need a helper board to handle valvetronic.

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There is no way to do it with position feedback in our current firmware.  Something like this could be used:  https://www.pololu.com/product/3142  The ECU boost solenoid PWM output can be set up to duplicate a "hobby RC servo" type position output to command this motor controller.  The motor controller takes the analog feedback from the position sensor and handles the closed loop position control onboard.

I've never used one personally but in theory it should work.

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