Title says it all. How does it work. I have an avh 5500 and want to make my own bypass

It is basically a NO or normally open switch, power comes on, it waits a bit, the switch closes then re-opens. That is the regular micro bypass, the AVH 8400 requires a double pulse so same thing - power on, wait a bit, switch closes, switch opens, switch closes, switch opens. Not sure if the 5500 needs the single or double pulse. Also, I have a 4400 which needed a single pulse bypass but then I installed the separate nav module and it needed a double pulse bypass with the navigation installed.

Does this happen continually the sequence? I wang to make my own.

Ok so it looks like I am able to simulate the bypass with my arduino. Now I just need to finder a cheaper way to make it

i Have a avh-5500bhs and am interested in making my own bypass as well.

Can i just pulse 12 volts or negitive wire to the parking brake wire ?

how exactly does it work ?

i Have a avh-5500bhs and am interested in making my own bypass as well.

Can i just pulse 12 volts or negitive wire to the parking brake wire ?

how exactly does it work ?

Currently I am using a arduino and a transistor.  I am powering the arduino from the amp turn on wire from the head unit.  I just wrote a simple code to pulse to ground the ground wire.  Really easy

Here is the long awaited update.  Here are some photos of my bypass.  Cost me about 5 bucks to make. Its an arduino pro mini.  Its knock off arduino i got off ebay.  Once I have the code profected I post the code. I will be testing it tomorrow on my avh-x2600bt 

I had a 'regular' bypass that I had used for a Sony XAV-602BT that was just a relay.   Initially when I got a AVH-8500BHS I used my old bypass and put a switch on it so I could flip it the second time.  Ended up installing a Microbypass last week.   It's such a small convenient package I couldn't justify building my own.