Please.... figure this one out: Strange situation… Bottom line is, my deck won’t power up. But why? I’ll start with the setup. I have a Sony marine head unit with wired remote. The only thing coming out of the back of the head unit is the power/ground/remote wires, and a set of RCA outputs to an EQ/Preamp (Exile ZLD). The ZLD controls 3 amps. A mono Subwoofer amp, a 4 channel cabin speaker amp, and a 2 channel tower speaker amp.

Today I received a new set of Exile tower speakers and a two channel Exile amp to power them. I hooked up the tower speakers first, and tested them. Everything was fine. Time to install the amp.
I turned off the battery and removed my existing 2 channel amp. Because the new one was larger, I needed larger gauge power, ground and fuse. I removed the old wiring and fuse and replaced it with the larger gauge. I installed the amp, hooked up power, ground, remote, RCA’s and speaker wire. Double checked everything, then turned my battery back on and flipped the “stereo” switch on the dash.
My deck did not power on at all, so of course the amps did not come on either. I used a test light and checked the B+ (red) and Battery constant (yellow) for power and it had power right up to the deck. I switched off the stereo switch and the B+ turned off, just like it should. I double checked all connections, pushed the reset button on the deck, checked the fuse in the back of the deck and even traded it out with a known good fuse, etc. Nothing. I pretty much decided the deck itself was dead. At this point, I really wanted to get on the water, so I went to Best Buy and bought a $100 deck. Brought it home and hooked it up and IT WOULDN’T turn on!!

As a last test, I took jumper wires with alligator clips and hooked the red and black wires directly to a battery. Nothing else attached to the deck. Just power and ground. No lights of any sort.

Finally, I have a RCA to 30 pin cable attached to the ZLD as an auxiliary , so I plugged in my Iphone, hooked all my blue turn-on leads up to the red B+ (turns on with the "stereo" switch) pushed the AUX button on my ZLD pre-amp and everything worked absolutely perfect. (albeit without a head unit hooked up at all….. My Iphone is now in effect my head unit, controlled through the ZLD)

The question is, why won’t either of those 2 decks power up? It’s almost like as soon as I flipped the stereo switch, I blew up the deck instantly, but there was no sound, smell, spark, no blown fuses… nothing. Plus, I’m 99.9% sure everything is hooked up right. Plus, nothing changed, other than swapping an amp??? What the hell?