Welcome to the North American Subaru Impreza Owners Club Friday March 29, 2024
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > Electrical & Lighting

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 09-25-2022, 04:41 PM   #1
Andy342
Scooby Newbie
 
Member#: 493310
Join Date: Oct 2018
Vehicle:
2010 Sti

Default Can the charging voltage be turned down? 2010 STI

My car charges at 14.1 to 14.7vdc. Our forester did the same. This happens whether the car has just been started or driven for several hours. It doesn't drop below 14 no matter what I do.

The battery has evidence of acid leaking out from under the battery caps. If I do not wash the top of the battery every so often the battery hold down clamp shows a little rust.

Every other vehicle I have (from the 67 Toyota to the 2015 Honda) charges at 13.something vdc. No other vehicle shows evidence of overcharging.

I had this battery in a different vehicle for a while and it showed no evidence of leaking or overcharging.

Can this voltage be turned down somehow? Does the car need to run at such a high voltage? Is this just another Subaru thing that we all just deal with?

The battery is an AC Delco flooded battery. It is at least 4 years old and works fine.

Thanks for any thoughts.
* Registered users of the site do not see these ads.
Andy342 is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 09-25-2022, 06:12 PM   #2
cdska
Scooby Specialist
 
Member#: 458809
Join Date: Nov 2016
Chapter/Region: NESIC
Location: Boston
Vehicle:
05 blob, 02 bug

Default

People use rectifier diodes such as a 1n4007 on the battery sensing wire to increase battery charging voltage. I did this myself to my own car because it would typically charge at only around 13.0-13.5V. You could do the same but to the return wire to decrease charging voltage.
cdska is offline   Reply With Quote
Old 09-26-2022, 12:29 PM   #3
GoFrogs
Scooby Newbie
 
Member#: 507317
Join Date: Oct 2019
Chapter/Region: MAIC
Location: SW Ohio
Vehicle:
2019 WRX
Pure Red

Default

Quote:
Originally Posted by Andy342 View Post
Every other vehicle I have (from the 67 Toyota to the 2015 Honda) charges at 13.something vdc. No other vehicle shows evidence of overcharging. Thanks for any thoughts.
Is it a "voltage" issue or an "amp" issue? What is the amp rating on the Subaru alternator? (My research shows 110A)

What was the amp rating on the other cars you mentioned above?
Other research:
- 2015 Accord 2.4L 4-cyl: 110A - 125A; V6: 130A - 135A
- 2015 Civic 1.8L 4-cyl: 95A

I know ppl who would seek out higher amp output alternators to keep up w/electrical demand such as high-watt stereos, aux-lights, air compressors, or any other device with high current demands.

Is the battery vent tube clogged or blocked causing acid to vent out of the fill holes?

Good luck in your quest.
GoFrogs is offline   Reply With Quote
Old 09-30-2022, 05:47 PM   #4
Andy342
Scooby Newbie
 
Member#: 493310
Join Date: Oct 2018
Vehicle:
2010 Sti

Default

Quote:
Originally Posted by GoFrogs View Post
Is it a "voltage" issue or an "amp" issue? What is the amp rating on the Subaru alternator? (My research shows 110A)

What was the amp rating on the other cars you mentioned above?
Other research:
- 2015 Accord 2.4L 4-cyl: 110A - 125A; V6: 130A - 135A
- 2015 Civic 1.8L 4-cyl: 95A

I know ppl who would seek out higher amp output alternators to keep up w/electrical demand such as high-watt stereos, aux-lights, air compressors, or any other device with high current demands.

Is the battery vent tube clogged or blocked causing acid to vent out of the fill holes?

Good luck in your quest.

There's no vent tube. This isn't an old motorcycle battery.

I do know the difference between volts and amps. Amp ratings have no relevance here.

Thanks for bringing attention to the thread.
Andy342 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

All times are GMT -4. The time now is 09:49 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.

When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission
Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.