I did an install in my friends 2003 Toyota Tacoma today, he is keeping the factory deck in it, but I added on a 4 channel MTX amp, and am upgrading the speakers front and rear. I used a Scosche 4 channel LOC, and after hooking it up I am getting very bad engine whine, and turn on/off pop through the speakers. I grounded the input ground wire to the same spot under the seat that the amp is grounded to, any chance that could set up a ground loop? The whine continues even when the deck is off, but stops when the RCA's are unplugged from the amp. Any suggestions, apart from changing out the LOC? Thanks!

 

Well, sounds like it'c coming from the LOC or the RCAs.. Try running a ground from the LOC back to the same ground as the deck.

 

I had PAC OEM-2 LOC installed for a couple of months and there was no noise whatsoever and no popping. and it wasn't really grounded to the car just connected the speaker inputs and hooked up my RCAs. The PAC also has the remote turn on delay which eliminates the popping but I didn't really use that because there was no need.

 

Thanks for the info guys. I might actually take the LOC out, and track down some of the speaker input plugs, bypass the LOC all together. The amp actually uses Smart-Engage also, so I don't need to run a remote off the ignition wire like I did.

 

Thanks, will look into this.

 

Anybody locally have a pair of the speaker level input plugs that they could sell to me? Thanks!