Door Central Locking System

[Walter Graham Robinson]

Could someone take a look at this schematic and tell me what size and type of capacitor I should use in this application? The information page indicates to place a capacitor across the blue/green wires but it doesn't show what size or type. Neither does it show whether the capacitor should be polarised. If polarised, which wire (green/blue) would be positive? Anyone's learned knowledge would be greatly appreciated..!?

[stj]

Re: Door Central Locking System

thats the motor power, i presume they are trying to supress noise.
so it's gonna be polyester film or ceramic, something low like 0.22 or 0.47uf
it needs to be close to the motor - so you need 4 of them.
some of those motor modules already have a ceramic cap inside them.

[redwire]

Re: Door Central Locking System

I put one of those door lock modules in my old car and it used relays.
The cap(s) could be to help the module with arcing from the motor brushes, or the relays. I'm assuming the relay clicking arcs and can cause the module to crash. Solid-state mosfets H-bridge shouldn't care.
Ideal would be a cap across the motor feed and one on each leg to GND, so three caps total - one across blue/green, one from blue-GND, another green-GND.
But I'm lazy and would try just one film or ceramic cap like 0.1-0.47uF across the blue/green wires near the module. Adding one at each motor I think could make for messy wiring in the doors where dirt and water are, and then the insulation chafes and shorts etc. so it has to be done well.

I found it helpful to go to an auto wrecking yard and take some hardware like the rods, brackets or even the door lock motors from newer or similar make/model of vehicle, to save time and OEM motors are better than the chinese kit.

[stj]

Re: Door Central Locking System

dont take motors from a scrapyard, they have a limited lifespan.
they are only 5-10$ on ali-express

[Walter Graham Robinson]

Re: Door Central Locking System

Thanks for the answers. Your pretty cool red..!?