How can I control a 12V solenoid door lock - Pi Zero

Question

I have a solenoid door lock that requires 3 different voltages to operate - Unlocked Idle: Requires low voltage (6V) that'll hold the solenoid seated - Locked: No power (0V) - Unlock: 50-100ms pulse at full current (12V) to move the mechanism

I've been attempting to do this and failing. I've seen this work using x2 relays and x2 buck-converters and a Pi Zero. I feel like that's over-complicating it and I'm looking for a simple solution.

Here's what I drew up (I'm very new to this so bear with me)

I came to this after someone told me to use PWM and a single FET. But this did not work at all.

Edit: I also added a flyback diode to this after I drew it up, still nothing; the lock doesn't budge.

Answer 1

If your diagram is correct, the power supply +(Positive) is connect to the lock -(Negative). This will not work.

Also, I'm not sure how this is going switch from 6v to 12v. There is no 2nd relay/transistor in you diagram. You will have to either use a buck converter or a voltage divider circuit And a second transistor/relay.

EDIT: You could use a single relay with a 'Normally open" pole and a "Normally closed" pole. If relay is activated 12v... If relay not activated 6v... If transistor off, 0v