Turn signal interfering with factory amp

Hello, I don't think this specific problem has been addressed in the forums. I just had a Sony CDX-F7710 headunit with a CDX-636 changer installed into my 1995 Chrysler Cirrus LXi. There is now a problem that when I use the turn signals in the car, the factory amp cuts out in sync withho the turn signal. Sound still flows through the amp, but it is not very loud and there is no bass. It sounds kind of like popping in sync with the turn signal. This didn't occur with the factory headunit. The guys at Best Buy (where I had it installed) suggested that the difference is the fact that the Sony headunit has 4 Volt preouts, where the factory headunit would not have preouts with such high voltage. They think that the higher voltage is causing the factory amp to go into protect mode and want to rewire the audio in the vehicle completely bypassing the factory amp. I talked about the issue with my best friend and he felt that it was a grounding issue and that taking the factory amp out should not be necessary. I would like to have another opinion on this subject before I have something rather invasive done, such as rewiring the car. So, would the best solution be to rewire the vehicle without the factory amp as the guys at Best Buy suggest or would it be better to change where the amp is grounded? If the better solution is to change where the amp is grounded, how should this be done? I have the feeling that the amp is grounded in the same place as the remainder of the sound system and probably everything on the dash, including the turn signal. Should the ground point be changed for the whole audio system or could the ground wire (which connects to the amp in a harness) be cut and grounded to a bolt that holds the passenger's seat (under which the amp resides) in place. I would appreciate any advice on this.

the cheaper fix would be grounding. pull the radio and re-ground it. also re-ground the factory amp like you said. i would pull the door sills and run a wire from under the seat and ground it under the sill, with a self-tap.

where are the power connections made for the headunit, cd changer, and amp? if the hu and cd changer share the same power wires as the turn signal (not saying at this point they are) the pop in your speakers in sync with the turn signal could be caused by that. consider running fused power wires for hu and cd changer directly from the battery to eliminate conducted noise.

Hey I had the same problem when I did an install for a friend in a Dodge Dakoda. The factory head units really don't pull that much power and unfortunately the car companies like to run the dash lighting and turn signals on the same power wires to save money. The simple solution is to run new fused wire from the battery terminals to the head unit. If you still have problems with noise from other electrical devices ground your headunit in the same place that your amplifier is grounded at. That should solve all of your problems, hit me back with some info once you get it done. Oh and just to elaborate on what happened with my friend's truck- the dome light when out and the new headunit sortof blinked with the turn signal if it would even stay on for the moment.

On second thought though- your factory amp could be going into protected mode because of the 4v signal it is recieving from the new headunit. The only way to really fix that would be to bypass the factory amp like the Best buy people said. Here is what I would do, have them take two piece of wire and wire the head unit directly to the battery even if the waires have to pass through your window and onto the battery wth the hood popped. If the stock amplifier behaves correctly with the new head unit wired directly to the battery then your problem is solved and your not out a good factory amplifier. If that dosen't work then your looking at bypassing the factory amp and probably replacing it with another amp. I'd say your chances are 50/50 because I can't really jump in your car and say hay your power is kinda fluctuating on a very brief level that makes me think the new head unit is drawing too much power. A simple straight connect with the battery to the head unit should let you know really quick if that is the problem or if your going to be shopping for a new amplifier.

Thanks to all that replied. The audio equipment power is connected to the ignition somehow since it will only power on with the key in certain positions, but as to exactly where and how it's connected I cannot say. I haven't pulled the dash out to be able to see and the electrical diagram in the repair manual that I have really is not that helpful in determining that. I think I will try having done what Alien509 suggests with connecting the headunit directly to the battery because that would answer some questions on whether the amp will work with the headunit at all. I will post a reply once I come to a solution. Thanks again to all.