Radiator fans not working

CS1LANCERFAN

MEMBER
2002 MITSUBISHI LANCER
1.3L
4 CYL
2WD
MANUAL
37,800 MILES

Hi, both my radiator fans are not working on start or even after a decent drive. However both fans starts working when the AC is switched ON. The Ac regulates both the fans as I can see both switching ON/OFF as the AC kicks in/out. What can be the issue? I cannot drive without switching ON the AC. Thank you

Tuesday, November 11th, 2014 AT 9:37 PM

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

The radiator fan is controlled by a control module and a relay.
The control module is mounted on the back of the fan (see picture below).
The relay is located in the fuse block under the hood.

First you want to check the relay and verify it is good.

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

If the relay checks out then check the control module.
Remember to only work on the radiator fan area when the engine is cool. Also always be careful working around a radiator fan.
I have attached the testing procedure for the module for your reference.

Please let me know of any questions.

Thank you.

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