Hey everyone. I drive an 09 HHR, and i've been competing in car audio competitions for years.



As many of you know, with a high powered car audio system, you need proper battery voltage (13.8-15v). The HHR has PCM controlled voltage regulation, meaning while driving, sometimes i'm at a constant 12.8v which is unsafe to run my amps at.

My friend (has a cobalt, very similar electrical systems) told me that on the ground wire of stock battery, there is a current sensor plugged into the wire. Seeing as there is 500lbs of audio equipment blocking my cargo floor, I couldnt access my stock battery very easily, so I googled a picture and It looks like the HHR has the current sensor plug as well. It sends a current reading to the voltage regulator to tell it what voltage to charge at. I want to bypass this so my voltage regulates at a constant 14.4v.

Would unplugging the current sensor from the ground wire allow this to happen?

 

i think the only way your gonna be able to bypass the the pcm is to get a mechman or ohio gen they build there to bypass the pcm control

 

You have to bypass the PCM. No other way around it. Also, if your an audio competitor you should know that how far forward your box is, is killing your score. I had a similar configuration and moving it that far forward lowered my score by quite a bit. If I remember right it was around a whole dB.

 

so how do you bypass it?

 

Welcome to the site jeremy1 .

The guys that posted above have not been back to this site lately so , you may not get a reply from them.

 

12.8v is fine if you weren't running hifonics :)