Hi guys. I just picked up a 2008 Expedition XLT with the base audio (no sub, single CD). This is my first post in the Gen3 section. I used to have a 2002 and was involved in that section a few years ago.

I just installed a Clarion NX404 head unit to get navigation and bluetooth. After I installed the head unit the rear speakers are cutting in and out. About every 20-30 seconds they turn on at very low volume for about 5-10 seconds and then back off. The fronts are working fine.

I re-installed the factory single CD head unit and it powers the rear speakers fine. So, I went over the Crux SOOFD-27 wiring harness I used in order to make sure I had the rears are wired correctly. They are. Therefore, I think the problem is with the Clarion head unit.

I'm trying to determine whether the Clarion is malfunctioning or whether the head unit simply can't drive the rear speakers for some reason. I think it would be the former and the head unit is simply bad out of the box.

Can anyone tell me if a head unit that is capable of driving the front speakers would, for some reason, be incapable of driving the rear speakers?

Thanks,
Chris

 

Nevermind. The guys at Crutchfield helped me figure it out.

It turns out that the rear seat controls were still partially active. They were cycling on and off which is what was causing the on/off situation. Also, the volume for the rsc was starting out low which is why the volume level was low when it did cycle on.

I pulled the plug for the rsc and jumpered the rear speaker in pins to the rear speaker out pins on the same plug. Problem solved.

I'm not sure if the PAC harness would keep this from happening. It might.

Chris