Hey everyone, I think its time to get a few more gurus on this dilemma. So to start I have a 2014 GT Brembo pack with a base radio and no sync. My radio burnt out one day so I decided to do the OEM NAV install. It is all complete and fully functional with sync, mic, updated sync software, and maps. I installed a KTP-445U in place of the stock Amplifier. But every since I installed it I have been getting a loud pop in my speakers when I turn the car off, pull the key out and open the door which completely shuts the power to the receiver. I went a purchased a second receiver and KTP-445u and still have the same issue. I then added a PAC module which has amp turn on and RCA connections which After tonight I am not using. I still get the popping. I have separate power and ground aside from the the factory power and ground Lastly I am using the head unit amp turn on. Please if anyone "ford electronics tech" whatever has any resolve hit me up. I really appreciate your time and thank you in advance.

 

No one really?

 

I had the same issue. Couldn't fix it. I replaced the Alpine with the 2013+ OE amp.
LEXiiON

 

SO I might as well get the OEM amp then huh.

 

SO a little update before I pull the plug I found out that by pressing the selector button 3 and 6 it put the radio into diagnostic mode. I took a picture of the DTC stored. The only code that it throws that I cannot explain is Abnormal power, Loss of SWC2 range.

 

So I can't say for sure on our cars, as I haven't done an install on one yet, but when I installed a system on my Escape, I had the same thing. It's pretty common with Fords. Essentially the factory head unit amp turn on is 12v. Way too much for an aftermarket amp. You just need to wire in a resistor, inline with the amp turn on, to drop it down to whatever the Alpine amp can take (usually 2-5v). Give Crutchfield a call if you're not sure where to get the resistors - I believe they sell them with butt connectors all ready to go, should be plug and play for you.

 

I have a similar issue. I'm using the stock head unit with an aftermarket amp to power the mid subs at the bottom of the doors. You probably wired your aftermarket amp directly to a 12 volt source without using the turn on wire from the stock head unit. You have to do that because the Ford auxiliary turn on wire is 5 volts but the aftermarket amp turn on needs a 12 volt source. So I think that when the aftermarket amp powers off, it was still receiving some signal from the head unit, causing the pop. It's a timing issue. The fix might be to use a 5 volt - 12 volt switch. Run the head unit 5 volt turn on wire to the 5 volt side of the switch, which then opens the 12 volt side that sends 12 volts of power to the aftermarket amp. I am not an electronics guy, but this may be the fix. I am going to try it on my car in the spring. Now only if I can find that switch!

 

Brain fart this morning. Literally said the exact opposite of this lol. You're correct.

 

So everyone I finally got it. After research and trial and error my popping has stopped. What I did was installed the PAC unit from my radio and that signal is sent to my KTP445U via RCA. Once that is connected it is wired into the the other side of the radio connector from the car wire harness. Simply I opt out from using the speaker signal to a RCA signal to feed my speakers. My assumption is that the signal from the factory Radio is to high of a frequency for the filters.... so I get a filter discharge (pop). I hope I explained it as simple as possible.

 

this is the same way I fixed my popping issue..sound is back to normal also.