adding aftermarket amp to factory nav/audiophile

[El Duque]

I bought an OEM nav unit to replaced the stock radio on my '08 EB. I noticed that the bass is much lower with the nav unit. After poking around, I saw that if the nav unit (or audiophile, I guess) is programmed for a factory sub, which mine is, then there is an internal cross-over activated which cuts the bass and sends it to the sub.

So I have a kenwood amp and sub laying around, I just figured I would hook that up using a metra reverse wiring kit I bought, it has the 8-pin plug which plugs into nav unit and is supposed to be the sub output.

But I can't get it to work, there is no sound. I have the wiring diagram which shows 4 wires, two of them are sub + and -, one is shield (i don't know what that is), and the 4th is enable/clip detection. The enable/clip detection is only putting out around 5 volts so I can't use that as the remote turn-on, so I ran that from a another switched output.

but now I've read some stuff that says that if the radio doesn't detect an amp from the enable/clip detect pin, then it won't send a signal. Basically saying that only a factory amp would work using that plug. Has anyone done anything like this?

Thanks

 

[jad2411]

Wow! I had that same issue on Monday this week, so far I haven't been able to find anything hopefully someone will know :
Mine is a lincoln navigator HU with cd changer, and has the sub out.
My idea was to run the enable wire to a relay to act as the remote turn on, not sure if by doing that the HU will unlock the sub out signal...

 

[El Duque]

I read up on this a little bit more and found out that the signal coming from the sub-plug is already low-level. So what I did was some RCA-to-speaker wire from radio shack, and ran that to the amp. It worked! I am not using the enable/clip detect wire at all, there are two wires coming from the plug, sub + and sub -. I haven't wired up a switched 12-volt lead for the remote turn-on yet, but at least I know that the sub signal doesn't have to be unlocked. hope this helps

 

[jad2411]

it does, I thought that it was a hi level out, since I had read about people using hi-lo converters, so I used one and it did nothing.
As soon as I have a chance I'll try it direct, with no hi-lo.
Hopefully it'll work

 

[jrford]

When i added the sub ('04) i could only get sound if the stock sub amp was plugged in. At first tired using just the aftermarket amp but got no sound either. I only used the +/- signal, and didnt mess with the others wires. Since i already had the amp which supported line-out signal i just went that way using the stock amp.

 

[El Duque]

When i added the sub ('04) i could only get sound if the stock sub amp was plugged in. At first tired using just the aftermarket amp but got no sound either. I only used the +/- signal, and didnt mess with the others wires. Since i already had the amp which supported line-out signal i just went that way using the stock amp.

hmm, were you using a line-out converter?

 

[jrford]

so sorry, i meant to say 'speaker level inputs' It was a Pioneer . .
http://www.explorerforum.com/forums/showthread.php?t=246610
post #18 has a pic. Still going strong.

 

[jad2411]

so my sub died last week, yesterday I was taking it off and decided to try this, it didn't work, the signal directly from the HU to the amp was crap when I get a new sub, I'll hopefully get an amp as well and run it out of the line out in my current amp