Amp/sub not working with aftermarket radio

[PHRN86]

I have a 2012 civic coupe ex with the premium sound, no nav. I upgraded the factory radio to an alpine single din. I purchased the HDCC-01 harness as well as the AWSC-01 to retain factory steering wheel controls. The problem is, everything works except the amp and sub. Has anyone installed this harness with success? I contacted Metra and they are at a loss without physically looking at the car. I've tested all wires with a volt meter (specifically the wire harness from the head unit with the amp turn on). Fuse is good, amp/sub work if factory radio is hooked back up.

Thoughts??

 

[ADExternal]

There could be numerous reasons why it doesnt work. I would diagnose this starting with a visual comparison of the harness pin and the factory harness pins layout and see if theyre consistent. Then I would check if the deck has a preamp output for the hardness or if its sub RCA out online. Then check all the settings on the single din, some of them you need to enable sub option. If it still doesnt work then, consider putting back on the stock radio to make sure nothing short circuited and the sub is in fact still works.

 

[PHRN86]

Ive traced all wires and checked connections, I've consulted with Alpine to make sure there wasn't a setting I was missing, I've moved around the RCA jacks, I've looked at the pins to make sure none are bent, but I haven't physically matched them up harness for harness, as I wouldn't know which ones actually needed to be connected. I've also checked the stock HU and it works perfect on reinstall.

 

[Bulkybear]

Are you talking stock amp and sub or an aftermarket setup? The stock amp runs all the speakers, so if any are working the amp is on and working. From that point I would focus solely on the signal connection for the sub channel. Which should be rca connections on the Metra harness adapter.

 

[PHRN86]

Yes, talking stock amp and sub. I'm waiting on a new harness/module as they feel that may be the problem. I also noted that the speakers sound absolutely horrible and distorted anytime the volume is turned up a little, like here's too much base, but mids and lows are turned into the negatives on the HU, Hoping it's all part of this wire harness issue

 

[Hillstones]

Yes, talking stock amp and sub. I'm waiting on a new harness/module as they feel that may be the problem. I also noted that the speakers sound absolutely horrible and distorted anytime the volume is turned up a little, like here's too much base, but mids and lows are turned into the negatives on the HU, Hoping it's all part of this wire harness issue

According to Crutchfield, you may need additional parts for the HDCC-01, such as the Metra 70-1730 receiver wiring harness. You should call them to find out. It sounds horrible because you are making a mistake by keeping the factory amp. Since you bought an aftermarket stereo, rip out that crappy Honda amp and it will sound a million times better using the built-in amp on the Alpine head unit directly to the speakers. But you will have to replace the speakers too, because of the way Honda wired them into the factory amp. The Honda sub is complete crap and does nothing. You are not going to get any bass out of it anyway. The Alpine head unit and some nice coaxials for the doors and rear deck would sound way better than the leftover factory crap (amp and speakers). If you do that, you don't need the HDCC-01 or 70-1730 harnesses. Honda knows nothing about premium sound. The factory amp ruins everything with lousy built-in equalization for all channels. Keeping that will ruin the sound, even with your Alpine head unit.