line output converter white (left speaker) RCA's not wroking

[lakenrockstar]

i have put a total of 12 hours in my car audio install and its still not working right. i am installing a pioneer 1600w max amp with 4 alpine speakers using a scosche 4 channel line output converter so i can keep my stock head unit. I have all of the wires ran and have checked to make sure they are all wired correctly that i know of. i have all 4 speakers hooked up to my LOC then I have 2 sets of RCA's (2 white and 2 red) running to my amp. the white rca's on loc, which i'm assuming is where the problem is coming from are not working and are for both left speakers in my car. All of my speakers work if i move a working rca to each individual input on my amp though even if i use the white wire. I have tried switching out my RCA wires completely as well and it didn't fix the problem. all of my gain adjustments are turned halfway on the LOC and amp. If i change the sound to the left side of my car on my head unit i can hear very faint almost no sound coming from the speakers. another weird thing is that if i touch my white rca's to the inputs on my amp i can hear audible sound (but still very quiet) coming out of the speakers, but as soon as i plug it in i can't hear anything. sorry if i made this confusing, but i'm trying to give all of the details. any help would be great!

i should probably mention that i just tapped into my stock speaker wire to get signal from my headunit so i didn't have to take apart my dash, which would have been a real pain. from my amp i have all new speaker wire going to each speaker.

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[juanmgarza26 10+ year member]

its possible that you are mixing up the + and - on the wires... Im not sure if this would cause a problem but if your just tapping into your speaker outputs and winging which one is + or - MAY throw the signal off, I could be wrong, try and look online for your factory headunit wire colors... what I did in a vehicle where my friend just wanted it done QUICK I used a db link LOC a simple 2 channel one and only used signal from 1 speaker and used a y splitter, you could do this, tap into just one of your rear speakers and see if it works, which im more than sure will work... if you need more help or something pm me man

 

[keep_hope_alive Premium Member]

is the LOC the Scosche SLC-4?

what position is the switch? it should be in the Factory Amp if the stock system is a premium system (JBL, Bose, Infinity) or in the Line Out position if it's a basic factory radio. if it is in the common ground position it can cause problem with modern head units.

if you use your fader, and fade to front does it make a change?

swapping + and - won't cause the problem since it is 4 independent channels. polarity is important for the system to sound correct, so that should be verified.

since you may not know what to look for, please take pics of your connections where you intercepted factory wiring and connected to speakers. if you didn't remove the radio and you wired to each speaker, then you would have a pair of speaker wires running to each speaker. one from the LOC input to each speaker and one from the amp output to each speaker.

in the future, it's easier to get two harnesses (into car and into radio) to intercept factory head unit wiring. then that gives you a location to intercept factory wiring from the HU to feed the LOC and into the car to feed the speakers without having to cut factory wiring.

removing a head unit isn't a big deal, instructions are available on Metraonline.com, simply search for your vehicle and download the free PDF instruction manual for mounting kits. Metra also has the two wire harnesses (70-#### and 71-####)