Car Stereos: Head unit not feeding to amp, factory speakers, rca outputs

Question
QUESTION: Hi I have a Sony GT370s Head unit which is directly wired to the factory speakers. I also have a Sony 800w amp which has 2x 6*9s and a 12" Sub bridged. I can confirm the amp/6*9/sub setup is working as I did a direct feed from my iPod while the headunit was sending the remote signal to turn the amp on. The headunit drives the factory speakers fine, but does not send the signal via the RCA plugs to the amp. I have tested the cable and it is fine, the headunit is just not sending the signal for some reason. I have tried the reset button behind the faceplate and gone thru all the options, but it just doesn't want to feed. I can't figure it out!

ANSWER: Tom,  I would guess there is an option not turned on.  I would go through all menu items and look for any settings that may affect the RCA outputs.  It may be a "sub on" switch, or a "RCA on" switch, or a "line volume" switch, etc.  If you cannot find anything in the menu, then I would find the owners manual, and see if you can find the answer in there.  If both of those options have been expired, then the radio probably needs to be repaired.  To be sure, you can go to the Sony website and send them your question.  If it is a simple answer, they should reply with an answer for you.  Hope this helps, Scott

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QUESTION: Hi Scott,thanks for your response - I should have said - I've been thru the manual and tried what is in there. When going thru the options using 'select', the manual says there should be an option "SUB/REAR" to choose what you're feeding to via the RCA out, which simply isn't there. If the Aux cable had a short, would the head unit pick up on that? Any other ideas?

ANSWER: I have tried to look your model up online, and it is definitely an oddball.  I could not find a copy of the manual, which is what I was looking for.  I was thinking of a couple more options to try.  First, perhaps there is yet another option that turns the RCAs on.  Once they are turned on, the "sub/rear" option may come up then.  Second, if there is some type of short in the RCA connections, it may be shorting the radio, and causing the radio to go into safety mode.  Try unplugging the cable from the radio, then look to see if the "sub/rear" option shows up on the options menu.  If it does show up after the cable is disconnected from the radio, there is either a short in the wire or the connection to the amp.  Sometimes the outside RCA metal will touch the metal of the amp chassis and cause it to short the system.  I do believe that it is an over-the-phone fix.  If you can get Sony tech support on the phone, they should be able to tell you how to fix the problem.  Good Luck, Scott

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QUESTION: Hi again Scott, thanks for you help with this. I have found that I can access the SUB/REAR option when the unit is turned off, however am still having no joy.

Answer
Did you try and unhook the RCAs from the radio, then check the options menu?  If there is any kind of short in the RCA wires or connections all the way to the amp, disconnecting them will let the radio reset to put the "sub/rear" option back on while the radio is on.  It is starting to sound like that is the problem. Also, check the outside of the RCAs to the metal housing of the amp, and be sure they are not touching.  I am sorry you are having this problem, but that is about all I can think of.  Anything else would probably be an internal problem with the radio.  As I have already mentioned, sony tech support should solve your problem on the spot.  -Scott