Volts dropping with heat...
Thread Starter
☠☣☢ Semper Ebrius ☢☣☠
Joined: Jun 2001
Posts: 83,301
Likes: 4
From: Virginia
Cruise-In IV-V-VI-VII Veteran
St. Jude's Donor '06
Volts dropping with heat...
Okay, I don't know if this is a problem, but here is what I notice...
"Volts" reads 11.4 to 11.6 (doesn't fluctuate, just in that range) when the key is on, but before I start engine.
I have an Optima Red Top that is only about a year old.
After start, I show 14.2 volts.
As the engine bay heats up the volts steadily drop until I'm getting about 12.8 at idle.
This all seems to depend on engine bay temp (which is in turn affected by ambient temperature.)
The reason I ask is because whether or not my HID kit even turns on seems to depend on the available volts (not engine bay temp directly, as my kit is mounted where the air stays cool.)
So, is the voltage thing normal or a problem? Should I go yellow top? What are the drawbacks to the yellow top?
"Volts" reads 11.4 to 11.6 (doesn't fluctuate, just in that range) when the key is on, but before I start engine.
I have an Optima Red Top that is only about a year old.
After start, I show 14.2 volts.
As the engine bay heats up the volts steadily drop until I'm getting about 12.8 at idle.
This all seems to depend on engine bay temp (which is in turn affected by ambient temperature.)
The reason I ask is because whether or not my HID kit even turns on seems to depend on the available volts (not engine bay temp directly, as my kit is mounted where the air stays cool.)
So, is the voltage thing normal or a problem? Should I go yellow top? What are the drawbacks to the yellow top?
Melting Slicks
Joined: Mar 2001
Posts: 2,658
Likes: 842
From: New Jersey
The voltage regulator in the alternator changes the voltage depending on the temperature, higher when colder. This is because it takes a hgher voltage to charge a colder battery. This is normal, all cars do this.
Thread Starter
☠☣☢ Semper Ebrius ☢☣☠
Joined: Jun 2001
Posts: 83,301
Likes: 4
From: Virginia
Cruise-In IV-V-VI-VII Veteran
St. Jude's Donor '06
Originally Posted by Hool97
My HIDs had the same problem until i ran a direct line to the battery for juice. as for the above 
Thread Starter
☠☣☢ Semper Ebrius ☢☣☠
Joined: Jun 2001
Posts: 83,301
Likes: 4
From: Virginia
Cruise-In IV-V-VI-VII Veteran
St. Jude's Donor '06
Originally Posted by ersatz928
The voltage regulator in the alternator changes the voltage depending on the temperature, higher when colder. This is because it takes a hgher voltage to charge a colder battery. This is normal, all cars do this.
