I added a push button to my car's trunk release motor circuit so that the trunk can be opened with the car still on (Fobs disabled when on).
The trunk release motor is on a gear system with a return spring. Best I can tell (can't see), the designers used an 87/87a relay that operates the motor when triggered by the fob receiver, but is normally grounded to deal with the voltage generated when the motor winds back.
I added a button and a capacitor / resistor combo that allows a relay to be tripped for a 1/2 second operating the motor for a similar amount of time to the factory wiring, and I isolated the two from each other with two diodes.
They both work great, but I am concerned that since there is no longer a path to ground on both legs, when the motor is being wound back, that there may be a feed back issue that may damage something over time... should/can I add a diode or resistor to ground on the (+) leg of the motor... or am I over-thinking it?
Diagram...
The trunk release motor is on a gear system with a return spring. Best I can tell (can't see), the designers used an 87/87a relay that operates the motor when triggered by the fob receiver, but is normally grounded to deal with the voltage generated when the motor winds back.
I added a button and a capacitor / resistor combo that allows a relay to be tripped for a 1/2 second operating the motor for a similar amount of time to the factory wiring, and I isolated the two from each other with two diodes.
They both work great, but I am concerned that since there is no longer a path to ground on both legs, when the motor is being wound back, that there may be a feed back issue that may damage something over time... should/can I add a diode or resistor to ground on the (+) leg of the motor... or am I over-thinking it?
Diagram...
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