Now that my new radio is in, I have a problem with noise that I believe is coming from the alternator. At idle there is a high pitched sound that increases in pitch up to 1500 RPM, then goes away. It is not my sub amp, as when I disconnected it I still had the noise. I changed the ground for the head unit with no luck. Then I tried a filter that goes inbetween the RCA preamp wires, again with no success. I did notice that when I unplugged the 4 RCA wires for the main speakers, the noise went away, confirming that it has nothing to do with my sub amp.

I was told that Pioneer head units are notorious for this type of problem. But what should I do? It is quite annoying because in city driving, I am constantly starting and stopping at lights, then the noise starts up again.

Please, somebody, help me

 

This is not a Pioneer problem, it's an HHR problem (with amps). The grounding points on the HHR are very poor. When I installed my setup, with Alpine head unit, I had the same problem.

Others have had the same problem and it usually involves an aftermarket headunit and an amp pushing the door speakers. My noise was coming from the amp pushing the door speakers. I did several changes at one time so I'm not sure which one exactly corrected the problem, but this is how I fixed mine:

• Switch the head unit ground from the stock harness to a metal bracket on the console
• Shortened the negative cable on the amps
• Rerouted my RCA's from the drivers side to the passengers side
• upgraded my RCA cables $$$

This is what worked for me. It may or may not work for everyone. There are other fixes out there. Also make sure you're grounding points are not painted like my negative battery cable was. The bottom line is that the HHR grounding points have a lot of room for improvement!


Ng

 

I did a google and found some interesting articles. They also talk about problems possibly from a bad ground in the antenna wire. They said to try disconnecting it and seeing if the noise goes away. Then they make a ground insulating adapter for the antenna.

 

here is what i would do....
1. make sure headunit is grounded to straight metal, good metal to metal ground.
2. ground cable on amp should not be more than 3 ft. Mine is at 18 inches.
3. RCAS on passenger side, our battery cable runs from passenger side to drivers side, making this move around the rear seat. Chevy kinda stuck it to us here.
4. Make sure that amp ground is metal to metal. clean the grounding point down to bare metal, no paint. while you are there, clean up the ground for the battery.
5. If the above doesnt fix it, then get better RCA's streetwires zero noise 6 or 7's would do it or High end Monster Cables. I dont recommend buying JL RCA's just for the simple fact that you can get the streetwires or monster cables at $80, this is on the very high side, compaired to JL's $150+.

 

I just got some bad news. After trying different grounds, direct to batter connections for power, RCA ground loop whatever, and even adding another ground to the antenna I called Metra to see if they had any ideas. And they did. They said it is due to using the factory amplifier. The man I spoke to said he is very familar with the HHR and they all have alternator noise, about 1 on a scale of 1 - 10, with the factory set up. Using a better head unit increase the noise. In fact, I was able to reduce it by turning down the gain on the Metra adapter.

The cure-either use an aftermarket amp and ditch the stock one, or use the built in amp on the new head unit. In my case, he said that my Pioneer radio has much more power than the 'Pioneer' factory amp.

Of course, the problem is I either have to hook up my other amp (it is big and would not fit neatly next to the battery since it is 5 channel) or run 4 sets of speaker wires from the factory amp up to the radio.

Either way, I have to remove the panal to get to the factory amp and figure out which wires are for each speaker.

By the way, does anybody have a schematic of the wiring to the factory amp?

In the meantime, I simply turned down the gain on the Metra box and will enjoy less noise, with the side problem of less volume.

 

run a number 12 wire directly from the battery(-) to the radio...
(test first. run it exposed right over the seats n jus plug it into the radio to see if it stops.. in most cases it does, then jus hide the wire)

 

Thanks for the suggestion, Lefty, but 'been there, done that'. Originally I was powering it from the stock wires, then redid the main power line direct to the battery so I could listen to the radio without the ignition on. I even tried running the yellow constant wire to the battery to see if it would help, but no luck. I think I am destined to eliminate the stock amp.

My latest concern, though, is that if I do that, then how will the onstar and car phone work??? And the chimes and turn signals??? The only reason I bought the Metra kit was to retain them.

 

damn it worked great for me... u ran a clean ground and it didnt even lower the wine a lil bit? i by passed the stock grounds for the radio and the xm unit n ran separate wires straight to the battery... for some reason i had way more alt wine when xm was on then the radio...