Weird battery light issue - Club Lexus Forums


Weird battery light issue

Reply
 
 
 
Thread Tools Search this Thread
Old 01-09-16, 04:53 AM   #1
UNCJD
Rookie
Thread Starter
 
Join Date: Aug 2015
Location: North Carolina
Posts: 74
Thanks: 0
Thanked 0 Times in 0 Posts
Default Weird battery light issue

Battery light came on in my '95 LS400 while driving down the highway. Battery tested ok, but autozone said alternator wasnt charging. This was a new alternator, so i pulled it out and brought it back. Bench tested fine
So I put it back in. There had been a PS leak, so I fixed that. Found a loose connection at the 120A fusible link, so I tightened it. All fuses check out OK.
Battery light's still on.
Everything on the alternator is tight and the connections were reinstalled with dielectric grease. I haven't recently jumped it or been monkeying with the electrical system. Any ideas as to what I should check? Should I idle it a while and see if the light goes out on its own?
UNCJD is offline   Reply With Quote
Old 01-09-16, 03:43 PM   #2
oldskewel
Pole Position
iTrader: (1)
 
Join Date: Sep 2010
Location: California
Posts: 359
Thanked 9 Times in 8 Posts
Default

I would not trust the Autozone bench test results.

I once had a bad alternator test good at our local Pep Boys, that was actually bad - although I was not sure of it until putting the new one made everything good.

It's a problem if you're needing to rely on a bad bench test to prove for warranty purposes.

I would get a voltmeter and measure voltage at the battery when the car is off / idling / revved at 2500 RPM. That should tell you more.
oldskewel is offline   Reply With Quote
Old 01-09-16, 07:00 PM   #3
UNCJD
Rookie
Thread Starter
 
Join Date: Aug 2015
Location: North Carolina
Posts: 74
Thanks: 0
Thanked 0 Times in 0 Posts
Default

Quote:
Originally Posted by oldskewel View Post
I would not trust the Autozone bench test results.

I once had a bad alternator test good at our local Pep Boys, that was actually bad - although I was not sure of it until putting the new one made everything good.

It's a problem if you're needing to rely on a bad bench test to prove for warranty purposes.

I would get a voltmeter and measure voltage at the battery when the car is off / idling / revved at 2500 RPM. That should tell you more.
The alternator is definitely a player here. I thought I had it fixed, but it started doing this Exorcist crap out on the road like it did when the last alternator went bad. Checked under the car after dinner and what do you know...a new PS leak. Or a failed repair on the old one. What drives me nuts is, that's a new PS pump!
UNCJD is offline   Reply With Quote
Old 02-27-17, 05:02 PM   #4
tcbernert
Driver School Candidate
 
tcbernert's Avatar
 
Join Date: Sep 2014
Location: nevada
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
Default ground cable

check the ground leaving to the alternator. sometimes after time the plastic heat shield over the bolt heats up if the connect isn't tight. gets hot and causes electrons to go crazy. try to move neg cable to see if you can get some play. a lot of times a new alternator doesn't come with a new screw. I came across a situation where after removing the bolt the cable wasn't seated correctly and had a crack. by placing 2 washers and reseating cable problem solved.one way to test is when battery light is on touch match to exposed neg cable from alternator with match. if it ignites find way to tighten connection
tcbernert is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Battery Light shwalker07 GS - 2nd Gen (1998-2005) 6 02-27-17 09:35 PM
Alternator charging voltage nmnunna32 RX - 3rd Gen (2010-2015) 4 10-15-15 05:06 AM
Battery light wont go off after replacing alternator pigtail and alternator. TRENTIMUS GS - 1st Gen (1993-1997) 1 09-15-15 08:22 AM
95 SC300 Battery/Alternator Problem drareg Performance & Maintenance 0 07-31-15 12:06 AM
battery charging problem need help asap chucksc400 SC- 1st Gen (1992-2000) 3 03-23-15 03:23 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 Off
Pingbacks are Off
Refbacks are Off

Forum Jump


All times are GMT -7. The time now is 09:27 PM.


Copyright © 2000-2016 Internet Brands, Inc. All Rights Reserved
 
  • Ask a Question
    Get answers from community experts
What's your question?
Send