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Old 06-17-2007, 03:40 PM   #1
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HOW-TO: Getting that Stock Audiophile HU to turn on sub amp

I just installed my new RF Punch P2D4 10" sub and a RF Punch 600.1bd mono amp in my 2007 ST with the sony package to replace that dinky sony sub. It went really well except for one problem...

...the stock HU doesn't have a usable remote on for the amp!

The problem is that the sub turn on signal (a red/white wire) is only 5v, not enough to signal the amp to turn on.

Now, I tried to build an op amp buffer circuit as posted a while back to change that 5v line to 12v but I was not successful. So I came up with a simple fix for anyone that is retaining their HU but wants the amp to turn on and off with the car:

1) Remove the center dash fascia piece as per the directions available from the I.C.E. How-To FAQ.

2) Remove the HU from the console and disconnect all connectors from it.

3) Assuming you do indeed have the Audiophile package, cut the red/white wire from the smaller connector. You should notice that the smaller harness connector is for the sub amp as it contains the gray/black and white/black wires as well as the aluminum foil shielding and bare wire. DO NOT CUT the red/white wire from the larger connector as it is for one of your speakers!

4) Locate the green/yellow wire in the larger harness connect and cut it about 2 inches from the connector. DO NOT cut too close. We need to reconnect this wire down the line!

5) Splice the green/yellow wires back together while attaching the red/white wire to that newly formed junction. This wire is the radio ignition line and it supplies 12v to the radio as an on signal when the car is started or the keys are in the ACC position. When the procedure done, you should have this wire supplying power to both the HU and the sub amp turn-on line (red/white wire).

6) Reassemble the dash and HU

The red/white wire in the trunk should now produce 12v of power when the radio comes on! Verify that it works with a Multimeter.

Comments are welcome!

ST Crew #65
2007 Liquid Gray ST with SAP1
FocusSport CoolFlo Intake, Balance Shaft Delete, TruBendz 2.5" SS w/ Cat, FRPP Performance Springs
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