SPONSORED LINKS

Radiator fan always on

Tiny
JAMESLUCE
  • MEMBER
  • 2002 TOYOTA SEQUOIA
  • 4.7L
  • V8
  • 4WD
  • AUTOMATIC
  • 230,000 MILES
Radiator fan always on even when cold. I thought it was only supposed to turn on when gets to a certain temperature.
Tuesday, August 11th, 2020 AT 6:30 PM

9 Replies

Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 108,320 POSTS
Hi,

You are correct. It should turn on at a specific temperature unless the A/C is on. Is it only happening with the A/C on? Also, the defroster will do the same.

Pay attention to see if that is what is happening, and let me know.

Joe
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
+1
Tuesday, August 11th, 2020 AT 6:54 PM
Tiny
JAMESLUCE
  • MEMBER
  • 6 POSTS
No, it is on even when A/C is off.
Was this
answer
helpful?
Yes
No
Tuesday, August 11th, 2020 AT 7:00 PM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 108,320 POSTS
Okay, then either we have a short to power or there is an issue with a relay, or a faulty coolant temperature sensor.

Lets start by checking if there is a short to power. I need you to remove the fan relay to see if the fan turns off. If it does, then I need you to check the relay.

Here is a link that explains how to check a relay:

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

The relay is in the under hood fuse/relay box. I attached a pic to help you locate it.

Let me know the results.

Joe
Image (Click to make bigger)
Thumb
Was this
answer
helpful?
Yes
No
+1
Tuesday, August 11th, 2020 AT 11:53 PM
Tiny
JAMESLUCE
  • MEMBER
  • 6 POSTS
Okay, I remove the fan relay fuse then started the car fan stayed on. Okay, put finger on relay fuse had someone else started I felt a click. And I remove the fuse started the engine and fan still ran.
Was this
answer
helpful?
Yes
No
Wednesday, August 12th, 2020 AT 11:27 AM
Tiny
JAMESLUCE
  • MEMBER
  • 6 POSTS
Should I move onto the temperature sensor?
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Thursday, August 13th, 2020 AT 9:52 AM
Tiny
JAMESLUCE
  • MEMBER
  • 6 POSTS
Ignore that last message I was holding the wrong relay. I found the right relay felt no clicking pulled it out and fan still ran. Bought new relay put it in still the same thing happening.
Was this
answer
helpful?
Yes
No
Thursday, August 13th, 2020 AT 3:21 PM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 108,320 POSTS
If you are removing the fuse, it shouldn't run. That indicates you have a short to power. When the key is on, another circuit is powering the fan. That is what I believe is happening on your findings.

Check as much of the wiring near the fan and make sure there is nothing wrong or causing this to happen. If you find nothing, then we need to remove one fuse at a time to see when the fan stops. At that point, we will at least know the circuit that is causing the problem. I will then look through schematics to see if I can locate areas where the two systems are close.

Let me know.
Joe
Was this
answer
helpful?
Yes
No
Friday, August 14th, 2020 AT 12:21 PM
Tiny
JAMESLUCE
  • MEMBER
  • 6 POSTS
Okay, thanks will do.
Was this
answer
helpful?
Yes
No
Friday, August 14th, 2020 AT 12:45 PM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 108,320 POSTS
No problem; happy to help. If you have a chance, let me know what you find.

Take care,
Joe
Was this
answer
helpful?
Yes
No
Friday, August 14th, 2020 AT 5:01 PM

Please login or register to post a reply.

Related Cooling Fan Content

Sponsored links