I ordered these $3 motion sensors from China I don't remember when, they just came this week, I had sometime at lunch to test these out. It seems to work quite well. I may have this trunk open by kicking the bumper somewhere... this summer :-) Slowly but surely.
I don't really know what I ordered... I have to look for
the record, but I remembered this one will work at low light also. When I get the relays and stuff to actually open the trunk, I think I mount this inside the trunk and drill a tiny hole for sensor to see. Now, I have to look for a relay that triggers at 3.3V, if not I have to built the 1 shot amplifier and I don't want to do too much... :-)
I do have some plumping tub laying around, good idea too. Jake!!!
How the heck they can sell these circuits for $3 (actually they charged shipping)? I can't even build these for less than that myself.
This circuit will trigger a relay of 12V or Ground
Originally Posted by dvs_dave
Handy. What circuit will you tie it into?
Also you will need to ensure it only works when the vehicle is unlocked, stationary, and only with people, not pets etc. I would think another PIR in the rear screen would solve that last issue?
Tied to the electric trunk latch that we currently use on our A8. I need to measure the latch voltages to see which one actually release the trunk latch and turn on the motor. I bet it's a 12V transferred to a pin on the latch when we press the latch, if that's the case, this one must latch the same 12V to the activating pin.
While the trunk is opened, I'll look into the close button on the top also, I want to press the remote to close the trunk while it's opened.
The safety thing is easy when the other one works.
While we're driving, we don't want the trunk to pop up? I'll disable the power when the ignition is on.
I want to make it simple so everyone can build without much problems...
Mods: Lowered approx 10mm all around (Sport is already ~20mm lower that non-sport), Auto open and close windows and sunroof via remote, Seat belt chime delete, Cross-drilled front rotors, Painted Brake Calipers, Rear H&R spacers, Fogs as DRL (yellow), Trunk Close via Remote (Thanks Louis), Parking Brake (ROW) auto release upon pressing accelerator (thanks Mishar) and Illuminated Door Sills. Future mods as I get inspired...