Chevrolet Cruze Forums banner
1 - 12 of 12 Posts

·
Registered
Joined
·
9 Posts
Discussion Starter · #1 ·
I have a 2014 LTZ and decided to upgrade the alternator to better power my amps. I had previously upgraded the battery to a duralast platinum H7, and done a big 3 upgrade with 1/0 wire. I purchased a 270 amp alternator from CES. They have been great to work with. When I first installed the alternator, I was only getting 13.4 volts. The PCM wire is not connected, as CES doesn't have a male side on the alternator as it would only reduce the benefits of a HO. I had managed to strip the bolt on the back so I sent it back to get a new rectified and check on the voltage. It bench tested at 14.4. They fixed everything and increased the voltage to 14.8. I got it back and took it to a different mechanic to install today. Now Im getting 13.8 volts, but still not what it should. I also had them replace the automatic tensioner to make sure it wasn't that.

Below are images of the alternator and the battery. The original power cable is connected as it was stock. Then the 1/0 wire runs from the alternator to the same spot on the battery as the original. My understanding was that I needed to leave the original wire as it would run the starter. Any ideas why I'm seeing lower voltage or what I might have done wrong?

Auto part Fuel line Engine Vehicle Suspension
Wire Auto part Electrical wiring Technology Electronic device
 

·
Premium Member
Joined
·
8,011 Posts
How is the battery ground connected? The stock battery ground cable has a small wire that goes off to the computer for voltage sensing. There's also a "donut" around the big cable to ground. The computer uses that to measure the battery charging current. Either could cause the computer to command a different voltage.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #3 ·
When I did the big 3, I added the bolt to the engine and ran a 1/0 from the engine. Then added a 1/0 from the negative terminal. So there are three wires coming off of the negative terminal.

Water Auto part Fuel line Engine Metal
Auto part Brake
 

·
Premium Member
Joined
·
8,011 Posts
So, it looks like you've bypassed the current sensor. I'd think it would cause an overvoltage instead of under, but perhaps the computer knows something is wrong.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #5 ·
Is this the donut sensor? I was looking online and this looks like what was being referenced by others for the voltage sensor. It's just father down. Wire Auto part Technology Bumper Engine
 

·
Premium Member
Joined
·
8,011 Posts
Yes. That's measuring the current in that wire. In a stock setup, that would be measuring all the current going to/from the battery with the exception of a small wire going to the computer. But your upgrade is bypassing that.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #8 ·
I used heatshrink when I first installed but apparently it was cheap as it all melted under the heat. I’m ordering new heatshrink from illcustomz to replace it.
 

·
Registered
Joined
·
9 Posts
Discussion Starter · #10 ·
Did you replace the stock wires with 1/0 or just add the 1/0? I added the extra wire but now am wondering if that’s part of the issue. I’ll try running it through the donut.
 

·
Registered
Joined
·
53 Posts
I left all the factory wires and added the 1/0. I have 2 runs going to the alternator, additional ground on the core support, additional ground going to the trans mount. then 4 runs of positive and negative going to the back.
 

·
Registered
Joined
·
112 Posts
I would ditch the stock negative battery cable altogether and replace it with a 1/0 cable routed through the sensor ring. Should operate as designed after that.
 
1 - 12 of 12 Posts
Top