C5 Tech Corvette Tech/Performance: LS1 Corvette Technical Info, Internal Engine, External Engine, Tech Topics, Basic Tech, Maintenance, How to Remove & Replace
Sponsored by:
Sponsored by:

Mini alternator questions

Thread Tools
 
Search this Thread
 
Old Sep 25, 2015 | 12:49 PM
  #1  
Almost_There_1's Avatar
Almost_There_1
Thread Starter
Instructor
10 Year Member
 
Joined: Oct 2012
Posts: 174
Likes: 12
From: Amarillo, TX
Default Mini alternator questions

Hello how's it going! Does anyone know of a mini alternator that works with the c5 pcm?

The reason I ask is because I currently have a Mexico reman alternator (autozone special) that I put in a few months ago, and every time I start the car I get the "charge system fault" message on the dic. It appears that the battery will not charge unless I give the throttle a quick blip above 2200-2500 rpms. I tested this by going for a drive and shifting before 2000rpms, and it drained the battery. A quick jump start and rev to 2500, and it charges perfectly (dic message always goes away on its own).

A stock alternator is out of the question because it won't fit with my Tt kit that I will be doing over the winter. I know the ptk kits use a mini alternator but I couldn't don't any info on which one most people use, and more importantly if I will still have the same issue? If I still will have the same issue, I plan on running a ford alternator in the ac location to save a few bucks.

Any help is greatly appreciated. Thanks in advance!
Reply
Old Sep 25, 2015 | 08:01 PM
  #2  
lionelhutz's Avatar
lionelhutz
Race Director
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Apr 2007
Posts: 11,150
Likes: 890
From: South Western Ontario
Default

Since you're tuning, you should be able to turn off the monitoring of the alternator in the system settings. At that point, a simple 50ohm, 5W resistor connected to switched ignition power would energize most alternators. Or, use an idiot light to energize it.
Reply
Old Sep 26, 2015 | 07:45 AM
  #3  
dadaroo's Avatar
dadaroo
Le Mans Master
 
Joined: Mar 2011
Posts: 6,835
Likes: 302
From: Columbia SC
Default



The C5 only uses a 5 volt input to the rotor in the alternator to "flash" the stator field. Higher revs will allow it to flash if you don't have a C5 correct alternator.

The circuit you want to power is the Red 225 one that goes to terminal B as shown on the schematic. It is between the Gray wire and the empty cavity on the end.

Let us know if you need any more help.


Mr. Sam






Charging System
Reply
Old Sep 26, 2015 | 02:33 PM
  #4  
BigGun's Avatar
BigGun
Drifting
10 Year Member
 
Joined: Feb 2008
Posts: 1,596
Likes: 67
From: Bahama North Carolina
Default

Originally Posted by dadaroo


The C5 only uses a 5 volt input to the rotor in the alternator to "flash" the stator field. Higher revs will allow it to flash if you don't have a C5 correct alternator.

The circuit you want to power is the Red 225 one that goes to terminal B as shown on the schematic. It is between the Gray wire and the empty cavity on the end.

Let us know if you need any more help.


Mr. Sam






Charging System
Has anyone actually done this to prove it works?
Reply
Old Sep 27, 2015 | 06:59 AM
  #5  
dadaroo's Avatar
dadaroo
Le Mans Master
 
Joined: Mar 2011
Posts: 6,835
Likes: 302
From: Columbia SC
Default

Lionelhutz described how all alternators worked up until the "Smart" guys at GM had their better idea.
Reply
Old Sep 27, 2015 | 01:12 PM
  #6  
Almost_There_1's Avatar
Almost_There_1
Thread Starter
Instructor
10 Year Member
 
Joined: Oct 2012
Posts: 174
Likes: 12
From: Amarillo, TX
Default

Thanks guys. That's exactly the info I was looking for.
Reply
Old Sep 27, 2015 | 08:00 PM
  #7  
BigGun's Avatar
BigGun
Drifting
10 Year Member
 
Joined: Feb 2008
Posts: 1,596
Likes: 67
From: Bahama North Carolina
Default

Originally Posted by Almost_There_1
Thanks guys. That's exactly the info I was looking for.
Be sure to tell us how it works out. Still wondering if anybody has done this before. In theory it should work great but until it is actually done.....

Last edited by BigGun; Sep 27, 2015 at 10:20 PM.
Reply
Old Sep 27, 2015 | 09:10 PM
  #8  
lionelhutz's Avatar
lionelhutz
Race Director
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Apr 2007
Posts: 11,150
Likes: 890
From: South Western Ontario
Default

I've been told on tuner forums that it will work. The system settings is where you setup the PCM to work on different platforms. It makes sens that if you set the PCM to have a F-Body alternator for example then it won't do the checks for the Valeo.
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-1

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
story-2

Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

 Joe Kucinski
story-3

Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

 Verdad Gallardo
story-4

Top 10 Corvettes Coming to Mecum Indy 2026!

 Brett Foote
story-5

Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

 Michael S. Palmer
story-6

10 Revolutionary 'Corvette Firsts' Most People Don't Know

 Joe Kucinski
story-7

5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

 Michael S. Palmer
story-8

2027 Corvette vs The World: Every C8 vs Its Closest Competitor

 Joe Kucinski
story-9

10 Most Common Corvette Problems of the Last 20 Years!

 Joe Kucinski
Old Sep 28, 2015 | 06:51 AM
  #9  
dadaroo's Avatar
dadaroo
Le Mans Master
 
Joined: Mar 2011
Posts: 6,835
Likes: 302
From: Columbia SC
Default

Tuning out the PCM to monitor the alternator duty cycle has been done many times. That will prevent any Charging System Fault messages.
Reply
Old Sep 29, 2015 | 12:41 AM
  #10  
BigGun's Avatar
BigGun
Drifting
10 Year Member
 
Joined: Feb 2008
Posts: 1,596
Likes: 67
From: Bahama North Carolina
Default

Originally Posted by dadaroo
Tuning out the PCM to monitor the alternator duty cycle has been done many times. That will prevent any Charging System Fault messages.
Tuning out the message doesn't mean the alternator is working correctly. I was more interested in the wiring mod you suggested in post #3.
Reply
Old Sep 29, 2015 | 07:29 AM
  #11  
lionelhutz's Avatar
lionelhutz
Race Director
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Apr 2007
Posts: 11,150
Likes: 890
From: South Western Ontario
Default

Originally Posted by BigGun
Tuning out the message doesn't mean the alternator is working correctly. I was more interested in the wiring mod you suggested in post #3.

Hooking a replacement alternator up the same way as it came installed as an OE piece. Why wouldn't that work?
Reply
Old Sep 29, 2015 | 10:34 AM
  #12  
73Corvette's Avatar
73Corvette
Le Mans Master
 
Joined: Feb 2012
Posts: 6,644
Likes: 479
From: OK
Default

Reply
Old Sep 29, 2015 | 05:18 PM
  #13  
BigGun's Avatar
BigGun
Drifting
10 Year Member
 
Joined: Feb 2008
Posts: 1,596
Likes: 67
From: Bahama North Carolina
Default

Originally Posted by lionelhutz
Hooking a replacement alternator up the same way as it came installed as an OE piece. Why wouldn't that work?
I don't know of any reason it should not work. Just wondering if anybody has went this route and if there were any unforeseen problems.
Reply
Old Sep 30, 2015 | 08:01 AM
  #14  
Mickeyrx70's Avatar
Mickeyrx70
Melting Slicks
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Sep 2011
Posts: 3,498
Likes: 680
From: The beautiful Alabama Gulf Coast!!
Default

Reply
Old Sep 30, 2015 | 10:00 AM
  #15  
lionelhutz's Avatar
lionelhutz
Race Director
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Apr 2007
Posts: 11,150
Likes: 890
From: South Western Ontario
Default

Originally Posted by BigGun
I don't know of any reason it should not work. Just wondering if anybody has went this route and if there were any unforeseen problems.

I'm sure it's been done on many LS1 swaps over the years. The people doing swaps and customization just do it instead of worrying so damn much about any little change not working.
Reply

Get notified of new replies

To Mini alternator questions





All times are GMT -4. The time now is 04:03 PM.

story-0
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-1
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE
story-2
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

Slideshow: Ranking the top 10 Corvette engines by torque output.

By Joe Kucinski | 2026-05-05 11:58:09


VIEW MORE
story-3
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

Slideshow: A Corvette pace car nearly matching IndyCar speeds sounds exaggerated, until you look at the numbers.

By Verdad Gallardo | 2026-05-04 20:03:36


VIEW MORE
story-4
Top 10 Corvettes Coming to Mecum Indy 2026!

Among a rather large group of them.

By Brett Foote | 2026-05-04 13:56:44


VIEW MORE
story-5
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

Slideshow: the top 10 things Corvette owners want in the C9 Corvette

By Michael S. Palmer | 2026-04-30 12:41:15


VIEW MORE
story-6
10 Revolutionary 'Corvette Firsts' Most People Don't Know

Slideshow: 10 Important Corvette 'firsts' that every fan should know.

By Joe Kucinski | 2026-04-29 17:02:16


VIEW MORE
story-7
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE
story-8
2027 Corvette vs The World: Every C8 vs Its Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-24 16:12:42


VIEW MORE
story-9
10 Most Common Corvette Problems of the Last 20 Years!

Slideshow: 10 major Corvette problems from the last 20 years.

By Joe Kucinski | 2026-04-14 16:37:05


VIEW MORE