Radiator fans constantly running SOLVED!!! - ClubLexus - Lexus Forum Discussion

ES - 1st to 4th Gen (1990-2006) Forum for all 1990 - 2006 ES300 and ES330 models. ES250 topics go here as well.

Radiator fans constantly running SOLVED!!!

Thread Tools Search this Thread
Old 05-09-14, 08:07 PM   #1
Driver School Candidate
Thread Starter
Join Date: May 2014
Location: CO
Posts: 3
Thanks: 0
Thanked 0 Times in 0 Posts
Smile Radiator fans constantly running SOLVED!!!

First post here. Thought I would repay my findings as this group helped me narrow down and solve my problem. 1999 ES300 had the fans running all the time problem, after reading almost everypost in this forum and others on the net I found the problem and fixed it for free. As we all know both fans should run when the AC is on, and the selected temp low enough to make the compressor turn on. When AC is off no fans should run. Mine ran all the time when vehicle was running or the key turned to ACC. I tested all relays and connectors were good. I read one post inparticular that made the most sense regarding the AC pressure switch and how it commands the fans. After googling and reading enough sites I found a diagram regarding its location, found it on my car,and low and behold I found one of the 4 wires coming out out the plug was broken. This defaults the system into a safety mode of protecting against overheating by making the fans run continuously. After soldering the one wire everything worked like a dream. See the the pics. I thought about how this system works and and concluded that my situation pointed to the AC pressure switch or its connectivity. I was lucky enough after finding it that the plastic shroud around the 4 wires on the connector was somewhat ripped enough to expose the one broken wire for me to see. If the break was further down the line I might never would have found it.. The switch is connected to the receiver dryer just in front of the condenser in front of the radiator by the Passenger side headlight. Easy access.
Attached Thumbnails
Radiator fans constantly running SOLVED!!!-20140509_081747.jpg   Radiator fans constantly running SOLVED!!!-20140509_083416.jpg   Radiator fans constantly running SOLVED!!!-20140509_081506.jpg   Radiator fans constantly running SOLVED!!!-20140509_083656.jpg   Radiator fans constantly running SOLVED!!!-20140509_084238.jpg  

Last edited by opdes121; 05-09-14 at 08:20 PM.
opdes121 is offline   Reply With Quote
Old 05-10-14, 06:11 AM   #2
Join Date: Sep 2010
Location: nj
Posts: 126
Thanks: 0
Thanked 0 Times in 0 Posts

Thanks for the update.
hzt30 is offline   Reply With Quote

Related Topics
Thread Thread Starter Forum Replies Last Post
AC Magnetic Clutch not engaging Importer Performance & Maintenance 5 08-17-17 10:15 PM
DIY AC Compressor and Condenser/Drier replacement dcz GS - 2nd Gen (1998-2005) 52 04-18-16 05:24 AM
Understanding IS 300 Radiator Fans operation minitac10x IS - 2nd Gen (2006-2013) 1 02-17-14 08:21 PM
AC / Engine Cooling issue - please read if applicable HtownBlue RX - 2nd Gen (2004-2009) 8 12-19-13 10:32 PM
A/C fans not coming on? usoff89 LS - 1st and 2nd Gen (1990-2000) 3 07-01-13 04:55 PM

1999 , 98 , connection , cooling , diagram , es300 , fan , image , is300 , lexus , ls400 , nonstop , radiator , runs , tim

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 08:42 PM.

Copyright © 2000-2017 Internet Brands, Inc. All Rights Reserved
  • Ask a Question
    Get answers from community experts
Question Title:
Your question will be posted in: