Alternator Issues - with isolator - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat
GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat

Go Back   GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat > Pontiac Bonneville > Everything Electrical & Electronic

Everything Electrical & Electronic Have an electrical problem? Lighting, Alternators, gauges, DIC, HUD, etc? Post it here. Please post Audio problems in the Audio forum, and Engine control problems in the appropriate Mechanical forum for your year.

LinkBack Thread Tools Search this Thread
Old 03-14-2008, 04:04 PM   #1
Senior Member
Posts like a Corvette
Join Date: Jan 2003
Posts: 1,250
Thanks: 0
Thanked 0 Times in 0 Posts
bmsgaffer86 is on a distinguished road
Default Alternator Issues - with isolator

I am trying to finally wire in my isolator after a few years of having it just sitting in my engine bay.

I have everything wired up (correctly i might add, i checked it many times) and fired the car up and the alternator wont put out a voltage.

Before this it has always had a slightly low output and would dim with turn signals and such things but it would run fine. There is a sense wire that i hooked up to the alternator and the isolator output to compensate for voltage drop from the diodes. It doesnt make a difference whether that is connected or disconnected and it seems that the PCM is only putting about half a volt to the L wire on the alternator and best as i can tell, it should be +12.

Why would it WORK before the isolator and NOT after? the physical electric properties are the same, does the diode drop the battery voltage enough to cause the PCM to not send full voltage to the L pin on the alternator?
'94 Bonneville SE - 106k miles 6/1/07
bmsgaffer86 is offline   Reply With Quote

Similar Threads
Thread Thread Starter Forum Replies Last Post
Alternator pulley issues Richardyuyu1 1992-1999 1 09-17-2011 08:48 PM
isolator and 2nd battery questions..95 se install 88bonnsse Audio (and aftermarket electronics) 6 04-21-2008 06:25 PM
Whiney alternator - update - probably not the alternator vital49 2000-2005 11 02-05-2008 09:52 PM
Crazy-cheap isolator! radomirthegreat Audio (and aftermarket electronics) 2 12-12-2007 04:55 PM
Alternator problems! csprague 1992-1999 8 09-06-2004 11:51 PM

Thread Tools Search this Thread
Search this Thread:

Advanced Search

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
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -4. The time now is 01:22 AM.