Mddepasqua

around 4 months ago, I purchased a pioneer AVH 1300NEX Head unit for my 98 es . I bought a wiring harness and connected it all. All of it works fine and has worked fine. The only thing is a small hissing, and alternator whine. I read that you needed to bypass the amp, but I didn’t do that, and it sill works. What should I do to stop the hissing/alternator whine , and do I need to bypass the amp? The whine annoys me, and I just want to get rid of it. Thanks

cory143

Hi. About a year ago I had BestBuy install a Pioneer AVH 4200NEX. Aside from Android Auto being really buggy, all is good.

Obviously I'm not providing an answer for you but at least wanted to let you know it's likely not Pioneer-brand related.

Good luck.

crwys

You need to install something like this.
https://www.amazon.com/gp/aw/d/B01KHRBK2W/ref=oh_aui_i_sh_in_o1_img?ie=UTF8&psc=1
I wouldn't reccomend this product specifically because mine only worked for like 4 months or so and I started to hear the whine slightly again. I would spend l like $30-40 or so, get a good one. Maybe at your local audio store so you can exchange it easily if it gives you problems.

Mddepasqua

crwys

Just in case others come across this thread. I talked to a guy at an audio shop and he also suggested grounding the aftermarket stereo chassis to your amps ground wire.