1998 Expedition w/ Mach Audio System

Hello everyone...im running into a little problem... im trying to install an aftermarket amp and subs in a 1998 Ford Expedition .... it has the Mach audio system with the factory sub/amp located on the passenger side rear of the vehicle... i removed the factory amp and sub and i want to use the space to mount ,y new amp...i am going to still use the stock stereo so i had to get a speaker wire to RCA output convertor box.... i want to connect this box to the speaker wires that went into the stock amp...only problem is i cannot tell which wire is which....does anyone have a wiring diagram for the subwoofer/amplifier section of the stereo system for this vehicle ?  i have searched for days and i cannot find one...thanks.

anyone please ??  i checked the wiring diagrams section of this site and others and no one seems to include the sub and sub amp diagrams... i need these desperately....

Even if you're keeping the factory head- pick up a Metra harness for that car with the sub harness in it.  The instructions will tell you which wires to use for which years, then you can solder on your RCA's.My ex once told me I have a perfect face for radio.

can I ask why you got rid of the factory sub and amp but kept the factory deck? sorry, just ad to ask...Lathan Hites

"I'm sorry, without a credit card I'll be requiring a stool sample"

Because i wanted more bass than the factory unit had to offer.

kryp2nite26 wrote: Hello everyone...im running into a little problem... im trying to install an aftermarket amp and subs in a 1998 Ford Expedition .... it has the Mach audio system with the factory sub/amp located on the passenger side rear of the vehicle... i removed the factory amp and sub and i want to use the space to mount ,y new amp...i am going to still use the stock stereo so i had to get a speaker wire to RCA output convertor box.... i want to connect this box to the speaker wires that went into the stock amp...only problem is i cannot tell which wire is which....does anyone have a wiring diagram for the subwoofer/amplifier section of the stereo system for this vehicle ?  i have searched for days and i cannot find one...thanks.

You can run into all sorts of problems when working with the Mach 460 system - I'm currently having issues replacing mine (see thread - System Layout - Looking for input).

If the Mach 460 in your truck is anything like the system in the Mustangs...then the factory amps only operate the midbass drivers and sub. The mid/high range speakers are powered by the headunit. In order to get more low-end bump, the wires that provide signal to the sub amp need to be used to power your aftermarket amp/sub.

Leaving the factory headunit in place...along with the amp for the mids will cause less hassle than rewiring the entire vehicle.

i have actually solved all my problems... but one note... the factory amp turn on wire that Ford uses to power on its subwoofer amp only supplies like 4.3 volts... the MTX amp i wired in requires 12 volts to turn itself on. i even tried to use the factory power antennea wire and i got the same results....4.3 volts. i dont know why Ford does this. so i was forced to use a 12 volt switched wire from the back of the HU to turn on my amp. if someone has a better way to do this im all ears  :-)

You could use the factory 5 volt amp turn on to trigger a relay, which would send 12 volts to your amp.  86 to factory turn on, 85 to ground, 30 to fused constant, and 87 to your amp's remote terminal.My ex once told me I have a perfect face for radio.

Friggin genious !!   Thats really a good idea... i just dont know if i want to go through all that trouble... im ok with the amp not being switched on by the HU...