Okay. I’m a novice at aftermarket installation. I’ve done one before, but it was fairly straightforward. I have a 1999 F150 with an AM/FM/Cassette which I want to replace with a Kenwood KDC-MP435U stereo. The blue box store told me the proper wire harness for the installation was the Merta BB-1771. I got the harness ready and removed the factory unit from the dash. However, instead of the one plug I expected, there were two plugs (a rectangular plug and a square plug). An internet search turned up some info on a Premium Sound System, but references to the second plug said it was either for a multi-CD player (but the factory unit didn’t have any multi-CD controls) or a factory amplifier. I don’t know if I can still use the amp because I ran across something called a Premium Sound Bypass plug. My wife went to Wally World to check on this plug and brought back a Scosche FDK106 Connector. The package has a note that it can be used either with or without the Scosche FAI-3A Bose/Premium Sound Interface, which I guess has something to do with the amp. It appears to have RCA jacks on it. My Kenwood also has two wires on the back for a sub-woofer.

So, my questions are should I use the Merta wiring harness, the Schoshe FDK106 Connector or something completely different? Do I need to use the FAI-3A Interface and what will happen if I do or if I don’t? If I do use it, where should it be mounted? Did I bite off too much? It looked pretty simple, and may be, but I’m still confused.

 

Correct harness. The square plug is unused. Its for addtions to the stock HU.

 

Yeah looks like this one is the equivalent of the metra hraness 70-1770 for the older ford models

APPLICATIONS:

1985 - 1997 FORD AEROSTAR
1994 - 1997 FORD ASPIRE
1986 - 1996 FORD BRONCO FULLSIZE
1986 - 1990 FORD BRONCO II
1995 - 2000 FORD CONTOUR
1992 - 1994 FORD CROWN VICTORIA
1986 - 1997 FORD ECONOLINE VAN
1986 - 1996 FORD ESCORT
1991 - 1994 FORD EXPLORER
1986 - 1998 FORD F150
1986 - 1998 FORD F250
1986 - 1997 FORD F350
2000 - 2002 FORD FOCUS
2000 - 2002 FORD FOCUS ZX3
2002 - 2002 FORD FOCUS ZX5
1986 - 1986 FORD LTD
1986 - 1998 FORD MUSTANG
1989 - 1997 FORD PROBE
1986 - 1994 FORD RANGER
1986 - 1995 FORD TAURUS
1986 - 1994 FORD TEMPO
1986 - 1997 FORD THUNDERBIRD
1995 - 1998 FORD WINDSTAR
1986 - 1994 LINCOLN CONTINENTAL
1986 - 1992 LINCOLN MARK VII
1993 - 1995 LINCOLN MARK VIII
1986 - 1994 LINCOLN TOWN CAR
1994 - 1994 MAZDA B-SERIES
1991 - 1994 MAZDA NAVAJO
1986 - 1994 MERCURY CAPRI
1986 - 2002 MERCURY COUGAR
1986 - 1994 MERCURY GRAND MARQUIS
1986 - 1987 MERCURY LYNX
1995 - 2000 MERCURY MYSTIQUE
1986 - 1995 MERCURY SABLE
1986 - 1994 MERCURY TOPAZ
1991 - 1996 MERCURY TRACER
1993 - 1998 MERCURY VILLAGER
1993 - 1998 NISSAN QUEST

 

X2
do not need the do-dad from wally world unless you have factory subwoofer/amp

 

How do I know if I have the factory subwoofer/amp? Where would it be?

Also, if I don't have the "additions to the stock HU" you mentioned above, why do you think the square plug was plugged in?

Thanks.

 

cd changer...
u didn't mention what year and style truck u got

 

I have a 1999 F-150 XL. I haven't been able to find a CD changer anywhere in the cab and the factory unit didn't have controls for handling a cd changer.

At any rate, I used the metra harness and the new stereo seems to be working fine. Thanks, everyone, for the advice.

 

So wat adapter should I use for an 03 f150

 

hey!! Have you looked under your rear drivers side seat? My cd changer is!! Also I have yet to find a adapter, I’ve looked everywhere!! Help!