A K
Well-Known Member
I'm working out the kinks of installing a new headunit. After a relatively successful, I've run into two issues.
First, when I turn on the radio, the OEM sub pops. From searching, it appears that aftermarket decks use about a 12v power-on. So, a 12v-5v resistor from Radio Shack seems to be the easy solution. No questions here, but feel free to give an "Amen" if you've done this and have any words of wisdom--like where to mount the resistor behind the dash.
Second, I have the dreaded alternator/engine hum that reflects the RPMs from the rear sub. In addition, when the unit dims, I get an additional hum that does not change. So far, I've identified a few things I can change. First, I zip-tied the sub and deck harnesses together. I will isolate them tomorrow (so that the RCAs are away from any power and ground). Second, I will ground the headunit itself to the firewall and not to the OEM harness (I don't know where the OEM harness grounds, and it appears the longer the ground wire, the greater the chance for interference). Third, I will try to run a ground wire from the White RCA as it appears when I touch it, the hums go away (even if for a few moments). I'm hoping that I can simply wrap and tap to the firewall.
Now, for the weird part. When I twist the White RCA, the interference goes away for longer than I am holding it, but comes back. Is this due to me temporarily grounding it, or is it more likely the RCAs are shot? Crutchfield uses decent materials, so I am somewhat reluctant to immediately conclude that their cables suck.
Any comments/insight is appreciated.
First, when I turn on the radio, the OEM sub pops. From searching, it appears that aftermarket decks use about a 12v power-on. So, a 12v-5v resistor from Radio Shack seems to be the easy solution. No questions here, but feel free to give an "Amen" if you've done this and have any words of wisdom--like where to mount the resistor behind the dash.
Second, I have the dreaded alternator/engine hum that reflects the RPMs from the rear sub. In addition, when the unit dims, I get an additional hum that does not change. So far, I've identified a few things I can change. First, I zip-tied the sub and deck harnesses together. I will isolate them tomorrow (so that the RCAs are away from any power and ground). Second, I will ground the headunit itself to the firewall and not to the OEM harness (I don't know where the OEM harness grounds, and it appears the longer the ground wire, the greater the chance for interference). Third, I will try to run a ground wire from the White RCA as it appears when I touch it, the hums go away (even if for a few moments). I'm hoping that I can simply wrap and tap to the firewall.
Now, for the weird part. When I twist the White RCA, the interference goes away for longer than I am holding it, but comes back. Is this due to me temporarily grounding it, or is it more likely the RCAs are shot? Crutchfield uses decent materials, so I am somewhat reluctant to immediately conclude that their cables suck.
Any comments/insight is appreciated.
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