Stock amp and sub

I would have to say the amp for the sub is recieving too much power for it to handle. Usually a factory stereo does not put out as much power (watts) than an aftermarket. I read in a post concerning a MACH sound system that Ford put a saftey feature into the system so that if the volume was turned up too high, it would fade the bass so it would no blow the speakers/sub. However, I read that it was the actual factory head unit that did this. Hmmm..sounds like Ford put the feature in the factory amp also. I'm fairly certain the amp is in the back of the SUV. You might need to bypass it with a different amp. Hope this helps! Eric

This site *might* help you out. Take care, Eric

How is the factory sub amp connected to the new radio? First thing you need to do is install a 570 ohm resistor in the turn-on lead. The factory turn on runs at 5 volts and as you turn up the volumn on the factory system, the voltage increases which will decrease the output from the factory sub amp. It is a clip detect system to prevent damage to the sub and amp. The 570 ohm resistor will prevent the amp from freaking out with the 12 volt turn-on signal. And like said by others, you may be over driving the factory amp inputs. Won't know until I know how it is hooked up now.Best Regards,

Rich