Coolant fans

Tiny
SCOTTBORDEN
  • MEMBER
  • 1991 BUICK REGAL
  • 3.8L
  • 6 CYL
  • 2WD
  • MANUAL
  • 100,000 MILES
My coolant fans run if I run direct power to them. I replaced both relays and that did not work. Now I have what I believe is called a coolant sensor? I cannot find it on my car. Do you think this is my problem? Thanks, Scott
Do you
have the same problem?
Yes
No
Wednesday, March 1st, 2017 AT 3:00 PM

4 Replies

Tiny
CARADIODOC
  • EXPERT
What is the problem? Do the fans never turn on? Do they never turn off? Is the engine overheating?
Was this
answer
helpful?
Yes
No
Wednesday, March 1st, 2017 AT 3:06 PM
Tiny
SCOTTBORDEN
  • MEMBER
They do not turn on. The fans that is. At idle overheats.
Was this
answer
helpful?
Yes
No
Wednesday, March 1st, 2017 AT 3:17 PM
Tiny
CARADIODOC
  • EXPERT
You have two separate but interconnected fan circuits with three relays. Start by finding fan relays one and two. Pull them out, then check for voltage in the sockets. Each one should have twelve volts on just one terminal. Now turn the ignition switch to "run". You should find twelve volts to a second terminal in each socket. If you have twelve volts on those four terminals, try switching the relays around. Failure of two at the same time would be very unusual, but one could have failed a while ago and you might never have noticed it.
Was this
answer
helpful?
Yes
No
+1
Wednesday, March 1st, 2017 AT 6:10 PM
Tiny
WRENCHTECH
  • EXPERT
Hi Doc, Let me point something out here.
Make sure you are not looking for a problem that does not exist. This car is designed to get hotter at idle. The fan is not even programmed to come on until approximately 226-228 degrees which can seem very high on the gauge, but is completely normal.
Try unplugging the coolant temperature sensor with the engine running. That will probably set a code that will have to be cleared later. If the fan starts them, you do not have a problem.
Was this
answer
helpful?
Yes
No
+1
Thursday, March 2nd, 2017 AT 4:23 AM

Please login or register to post a reply.

Recommended Guides