i've heard of people doing the same trick, but im hearing mixed results. i have 4200's coming in next week, so ill figure it out as soon as possible to verify that it works. then ill post a video.

I should be getting my 4200 in tomorrow. I'm curious to find out if this little trick will work for it as well! Thanks for the info.

I am trying this with my 4200 tomorrow. i feel like an idiot, but I watched allyn's video on youtube about the 4100 bypass and am just clarifying, that out of the 2 grounds coming out of the 87 position, one goes to the car and the other to the head unit, right? Thanks.

I did this for my 4200 and it's working great while the unit is on. The problem I'm having is when the unit is off. I go into, or try to go into, the menu for functions etc, and it gives me a message saying that function cannot be operated while in motion. So to me it's not reading the relay bypass and I'm guessing that's because the remote wire is not on because the unit is not on.

My solution to this is to attach a separate wire from the ignition on a switch. So you then have a remote wire and an ignition switched wire on the same pin. So when the unit is off, you push the switch on and the relay is activated as is the bypass. When you don't need this mode you keep the switch off because you have the remote for standard use.

Does this make sense and do you guys agree? Would I need to add a diode or anything to the remote wire so that current from the ignition wire doesn't travel up the remote wire? Or does that sound like an issue to worry about?

The remote wire should click back on when you activate the function menu, even if the unit is off.

Does anyone know it is an issue with creating a constant draw on the battery by installing a bypass on the avh-p 4200?

Geoff - No, there will only be a draw when the head unit is on, because the relay is only getting power from the head unit's remote turn-on wire which is only active when the unit is ON.

It's not working with the function pushed and the unit off. It keeps giving me the same message about the unit not operating when in motion or whatever it is. So that tells me the remote wire doesn't go on with the unit off. Which makes since cause the unit it self might be on but it wouldn't send a signal out if the functions weren't on. Still puzzled on this one.

When you hold down function with the unit off it should click the relay on as the menu pops up. The unit is essentially turning on when it goes into the initialization menu. Next time I install one I'll confirm that.

I currenlty use the same relay to turn on multiple amps in my setup. Can the green parking brake wire be integrated into it or will i need to wire in a second relay? I use 87 to amps, 86 remote, 85 ground, and 30 to12 volt.

no. you would have to use a second relay.

Does it matter what kind of 12V relay i'd use? Like in Amp?

where the black wire connects 87 86