Conversions & Swaps LSX Engines in Non-LSX Vehicles
Sponsored by:
Sponsored by:

alternator charging problems.

Old 02-11-2008, 02:24 AM
  #1  
Teching In
Thread Starter
 
aziza z's Avatar
 
Join Date: May 2007
Location: So cal.
Posts: 40
Likes: 0
Received 0 Likes on 0 Posts
Default alternator charging problems.

Just finished my swap just recently and while driving the car died and wouldnt start. I later found out my alternator wasnt charging. Thinking it was the alternator i switch it out for a new one. same thing happens. the car wont keep charge. i have one of those battery chargers/testers that tells if the alternator is charging and it says it isnt. It has only one wire that goes on top of the alternator (small red wire). after some reading i found out that this is the exciter wire that should have 12vs. it doesn't.


anyone know whats wrong here? any help is appreciated.

oh yea its an ls1 from a 2002 camaro ss.
Old 02-11-2008, 02:36 AM
  #2  
8 Second Club
iTrader: (1)
 
1dirtyZ's Avatar
 
Join Date: Nov 2001
Location: the not so stock tribe
Posts: 3,697
Likes: 0
Received 0 Likes on 0 Posts

Default

i know that the wire has to have a 12v ignition-on source going to the alternator so it starts charging.

what is the swap we're talking about here?
Old 02-11-2008, 02:43 AM
  #3  
Teching In
Thread Starter
 
aziza z's Avatar
 
Join Date: May 2007
Location: So cal.
Posts: 40
Likes: 0
Received 0 Likes on 0 Posts
Default

ls1 into a Datsun 280z in my sig.

The harness was reworked by speartech. I have been unsuccessful with contacting them with this problem though. The wire is not getting the 12v it needs.
Old 02-11-2008, 03:36 AM
  #4  
8 Second Club
iTrader: (1)
 
1dirtyZ's Avatar
 
Join Date: Nov 2001
Location: the not so stock tribe
Posts: 3,697
Likes: 0
Received 0 Likes on 0 Posts

Default

sorry, i just saw the other thread you had
nice project by the way!

i'm not 100% positive, but the speartech harness does not come with a plug for the alt. ( if i remeber correctly)

on my mustang i just took the original wire going to the ford alt. and used it for the GM alt.
Old 02-11-2008, 04:21 AM
  #5  
TECH Junkie
iTrader: (18)
 
LS1MCSS's Avatar
 
Join Date: Jan 2006
Location: Dover, Arkansas
Posts: 3,831
Likes: 0
Received 7 Likes on 7 Posts

Default

Try running a wire from a switched 12V source to the alternator, but make sure you put a 470 ohm, 1/2 watt, resistor inline before hooking it to the alternator. With straight 12 volts running to the alternator, it won't last long.
Old 02-11-2008, 07:48 AM
  #6  
DCx
TECH Regular
iTrader: (12)
 
DCx's Avatar
 
Join Date: Jan 2007
Location: San Bernardino CA
Posts: 416
Likes: 0
Received 1 Like on 1 Post

Default

i tried the resistor route and it didnt work. so i added a small light bulb i pulled from one of my autometer gauges. ran it in line to the alternator. it started charging right away. my set up is only temporary but here are some pics.

here is the terminal on the alternator



run a bulb in series like this



when you key over the ignition the bulb will light up. when you start the car the light will go out. if your alternator doesnt charge the light will turn on again letting you know. im going to run mine inside the car.
Old 02-11-2008, 09:34 AM
  #7  
Teching In
Thread Starter
 
aziza z's Avatar
 
Join Date: May 2007
Location: So cal.
Posts: 40
Likes: 0
Received 0 Likes on 0 Posts
Default Speartechs replied

sent an email to speartech: this is the response.

Speartech <speartech@insightbb.com> wrote:

What you are reading is completely wrong. 12 volts on the red wire will destroy the regulator inside the alternator.

You would need to check continuity of the red wire from the alt. connector back to the PCM connector (PCM RED 15). If that is good the problem is either with the computer or other wiring on your car.

John
Speartech Fuel Injection Systems, Inc.
www.speartech.com



--------------------------------------------------

thing is that when i have it pluged into the pcm like instructed the alternator doesn't hold its charge. what else could be wrong? i alt is brand new.
Old 02-11-2008, 03:31 PM
  #8  
Teching In
Thread Starter
 
aziza z's Avatar
 
Join Date: May 2007
Location: So cal.
Posts: 40
Likes: 0
Received 0 Likes on 0 Posts
Default

dcx


i hooked it up that way and the light never comes on but it has power going thou it. (the bulb is good)
Old 02-11-2008, 04:10 PM
  #9  
sawzall wielding director
iTrader: (4)
 
G-Body's Avatar
 
Join Date: Sep 2004
Location: Downers Grove, IL
Posts: 3,120
Received 8 Likes on 8 Posts

Default

If the light never comes on and it has 12V going to it then the problem is with the alternator.

Turn the car to the run position (but don`t start it) the light should be on, if it is not. Then unplug the 4 pin plug from the alternator and ground pin B (the wire that goes to the lightbulb) If the light is still off you are either not getting power or the wire has a break somewhere. If the light lights up the problem is with the alternator, either it is getting a bad ground or is just bad. To see if it is getting a bad ground try grounding the plug to the case of the alternator, if the light is lit the ground is ok, if it is not lit....
Old 02-12-2008, 01:06 AM
  #10  
Teching In
Thread Starter
 
aziza z's Avatar
 
Join Date: May 2007
Location: So cal.
Posts: 40
Likes: 0
Received 0 Likes on 0 Posts
Default

well i feel stupid. the big wire in the back was loose.


problem solved. thanks guys.
Old 02-12-2008, 04:04 AM
  #11  
DCx
TECH Regular
iTrader: (12)
 
DCx's Avatar
 
Join Date: Jan 2007
Location: San Bernardino CA
Posts: 416
Likes: 0
Received 1 Like on 1 Post

Default

awesome. my alternator is so close to my frame stands i have to remove the alternator to get to the plug on the back. pain in the ***.
Old 02-12-2008, 10:10 AM
  #12  
Teching In
Thread Starter
 
aziza z's Avatar
 
Join Date: May 2007
Location: So cal.
Posts: 40
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by DCx
awesome. my alternator is so close to my frame stands i have to remove the alternator to get to the plug on the back. pain in the ***.
haha yea same here. so i just lifted the car and did it from under (which was not much better)
Old 05-12-2008, 07:08 PM
  #13  
Teching In
 
ls1cutlass's Avatar
 
Join Date: Feb 2008
Posts: 39
Likes: 0
Received 0 Likes on 0 Posts
Default alternator not charging

Hey guys i got my resistor is 440 enough or should i use 508 i didnt get the 470 i got 4 of the 220 and 4 68 thanks for the help
Old 05-13-2008, 05:53 AM
  #14  
DCx
TECH Regular
iTrader: (12)
 
DCx's Avatar
 
Join Date: Jan 2007
Location: San Bernardino CA
Posts: 416
Likes: 0
Received 1 Like on 1 Post

Default

screw the resistor. i tried so many times to get it to work. just splice in a simple light bulb and be done with it.

i used a spare turn signal pig tail from autozone, then finally settled on a bulb that belongs in an autometer gauge.
Old 05-13-2008, 05:57 AM
  #15  
DCx
TECH Regular
iTrader: (12)
 
DCx's Avatar
 
Join Date: Jan 2007
Location: San Bernardino CA
Posts: 416
Likes: 0
Received 1 Like on 1 Post

Default

your Z is so sick!
Old 05-14-2008, 12:59 AM
  #16  
Teching In
Thread Starter
 
aziza z's Avatar
 
Join Date: May 2007
Location: So cal.
Posts: 40
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by DCx
your Z is so sick!

Thanks. I love it. Especially with the ls motor. Handing super cars they're *** is a blast.


Thread Tools
Search this Thread
Quick Reply: alternator charging problems.



All times are GMT -5. The time now is 11:23 AM.