I located the 4wire harness under the cupholder middle console piece. this harness comes from the stock bose amp and goes to the stock bose subwoofer. I spliced into the 4wires using crimper connections, wrapped with electrical tape, used a line inverter to connect rcas to go to amp. These are the 4 wires that 2 local install shops confirm that are to tap in. I'm getting a rumbling from the subwoofer when the stock radio unit is off. No rumbling when RCA's disconnected so i figured noise is coming from rca signal. My ground is good to floor pan. So what's my best bet to get rid of this rumbling. I don't want to try a million things. I've heard better grounding the stock radio. Should my line inverter/rca's be pulling signal from speaker output wires that are before the stock amp? Would that give me a cleaner signal? I've been trying to figure this out for 3 days straight. It's driving me nuts. Any suggestions?
