New HU in conjunction with OEM sub amp?

[chamill]

I am trying to figure out if I can use my aftermarket HU to power the factory amp on my 03 Eddie Bauer Explorer. I really want to avoid the expense of an addition amp right now, I’ve already got one powering the four front channels, and just want to fill in the bass for now. It doesn’t need to be too powerful

Here is what I’ve found so far:

The connector at the back of the radio (Mach) outgoing to the amp has the following pin labels:

1: Radio – Subwoofer, High (-)
2: Radio – Subwoofer, High (+)
3: Shield
4: Radio Subwoofer High Enable
5-8 not used

The connector leading into the amp has the following pin labels:

1: RX, Signal
2: Ground
6: Voltage Supplied at all times (overload protected)
7: TX, Signal
8: Radio – Subwoofer, Low, (-)
3-5,9,10 not used

I also did a meter test on the outgoing leads from the original stereo:

Front speakers out read about 6
Sub out reads 4.88

How can I use this information to assist me in connecting to a new HU? I have RCA outs for a subwoofer as well as the four front speaker connections available to splice into the harness.

Thanks for your help!

 

[chamill]

Well, I got it done and it sounds great! Really helped to fill out the sound.

I spliced an RCA cable into the wiring harness using the neg (shield of the RCA) from the left HU output and the pos (inner RCA wire) from the right HU output. Then spliced right into the ACC power line to power the amp. Turned it on and I've got nice bass!

I didn't have to use a loc because I've got 4v pre-outs that I was able to use. The HU allows me to select the crossover frequencies for the sub and also add or remove bass boost.

The only problem that I have noticed so far is that the amp doesn't have a soft power on, so I end up with a slight pop from the sub on power up. Is there any sort of line conditioner or anything like that that can be used for amps with a problem like this?