Radiator fan problems

Tiny
JAKE CURTI
  • MEMBER
  • 2010 MITSUBISHI LANCER
  • 4 CYL
  • 2WD
  • AUTOMATIC
  • 128,000 MILES
Today the first thing that I noticed was that my air conditioning started to run hot when I was idling in park. Next, my engine temperature light came on, saying it was overheating while parked. I knew that if it was a radiator fan issue, everything would start working if I started driving. I was correct, the engine cooled back down quickly, and my air conditioning worked. I’ve heard that if the fans motor is messed up, the fan will be locked. I am able to spin the fan freely manually. When I have the car on with the hood up, I don’t see the fans spinning at all, neither of them. The coolant fluid is not low. Also, I don’t know if this is related or not, but a few days ago I started to have loud/slightly vibrating engine sounds while idled in drive, not on neutral.

Saturday, June 4th, 2022 AT 6:04 PM

56 Replies

Tiny
KASEKENNY
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You should have two fans. Is that correct?

Basically, these fans are run through a number of relays. The fan that comes on when the AC is on is run through a condenser fan relay and then the other is a radiator fan relay. Both of these are powered through a fan relay.

So, we need to start by checking the fan relay.

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

All of these are grounded and controlled by the ETACS ECU. Basically, this is the climate control module.

So, let's start with checking the relays and then we can go from there.

Thanks
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Sunday, June 5th, 2022 AT 5:29 PM
Tiny
JAKE CURTI
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Yes, that is correct, two fans. Checking the relays now.
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Monday, June 6th, 2022 AT 9:20 AM
Tiny
JAKE CURTI
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Only one socket on this relay lights up, I also tested the other connectors (not sure what it's called), and not all of them light up either. I also tried to record the whining sound that I hear when the battery is on but not the engine. The relay itself looks fine.
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Monday, June 6th, 2022 AT 10:15 AM
Tiny
KASEKENNY
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Unfortunately, we are going to have to test the relays again. Sorry I wasn't more specific, but we need to check for ground on a couple of the terminals.

This means we need to move the clip on the test light to battery positive and then touch terminal 4 and 3 of the 5-pin relay.

However, what I would do before we get into this type of testing because it is confusing on what is power and ground, I would pick up replacement relays and just swap them out. They are pretty cheap so that is far easier than testing each one.

If that does not repair, it then we need to check and make sure each fan can actually turn on.

It is unlikely that both fans would fail at the same time. Also, it is unlikely that the radiator and condenser fan relay would fail at the same time. Which is why I think it will be the fan control relay (the 5-pin relay).

However, both fan motors did look in rough shape so that is a possibility. Maybe one of them failed a while ago and the vehicle has just been making it through on one fan. Now the other failed.

Again, I suspect the relay but let's try this and go from there.

Thanks
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Monday, June 6th, 2022 AT 4:02 PM
Tiny
JAKE CURTI
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I appreciate the help, no need to apologize. I don’t know much at all about cars, but I learn fast and will understand once it’s explained to me. I take it by connect to the negative I was just basically seeing if the light worked. Now by connecting to the positive and touching specific terminals and it lights up, it tells us it is grounded. Is that right? I was assuming the same thing; it would be very coincidental if both fans stopped at one time. I Doordash, so I drive a lot and I never noticed anything wrong with my air conditioning not working nor has my engine ever overheated while idling until now. I feel that if one went out, I would at least notice my engine running maybe slightly hot or my air not being as cold, but I haven’t until all at once.

I will stop by Meijer here in a bit and pick up a 5-pin relay, is this the only one I would want to try swapping? Then I will test again.
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Monday, June 6th, 2022 AT 5:26 PM
Tiny
KASEKENNY
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I think that is the place to start is with the 5 pin relay. That way we can eliminate that and start moving onto what else would cause both fans.

However, if that does not fix it then we are going to have to make sure they both come on. I will explain how to jump the relay for each fan if it comes to that.

Thanks for the update and let us know what happens and we can go from there.
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Monday, June 6th, 2022 AT 6:54 PM
Tiny
JAKE CURTI
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Meijer doesn’t have any relays, so I’ll have to go to AutoZone tomorrow.
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Monday, June 6th, 2022 AT 7:37 PM
Tiny
KASEKENNY
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Okay. Thanks for the update. If you can't find one quickly then I am attaching the testing for the actual relay. It is a little confusing, but we can work through it. The fan control relay (5 pin) is the last 2 attachments.
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Tuesday, June 7th, 2022 AT 10:21 AM
Tiny
JAKE CURTI
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AutoZone was not very helpful, the 5-prong relay I got fit into the spot, but it was not the exact same relay because we couldn’t find any part number. So, it plugged in correctly, but the fan did not come on. I'm not sure how universal the relays are and if that was the correct one to use, as the body of it was larger even though the prongs lined up correctly in the spot. Here is testing the fan control relay while attached to the positive side of the battery. Only 4 lights up. Should I test the condenser and radiator relays too?
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Tuesday, June 7th, 2022 AT 10:35 AM
Tiny
KASEKENNY
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Okay. So that means the ground for pin 4 is good.

Let's try something different. I am attaching the wiring diagrams from the OEM. They are a little better layout.

When you are testing electrical issues with a test light you are looking for a complete circuit which means the light will turn on.

So, you connect the clip to battery positive and in order to get the light to turn on, you need a good ground for the probe.

If you are probing the power source like pin 1, 2, 5 then the light will not come on.

In order to test these, you need to connect the clip of the test light to ground and probe the power source. This will complete the circuit.

However, let's try and jump the fan relay and condenser fan relay just to see if the fans come on.

Turn the key on and jump 4 to 3 on the condenser fan relay.

Then on the 5 pin, let's jump 5 to 4.

Lastly on the radiator fan 4 to 2. When the key is on both fans should be running.
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Tuesday, June 7th, 2022 AT 11:46 AM
Tiny
JAKE CURTI
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You lost me now, I think. Or maybe not. What I think you are saying is to attach the clip of the test light to negative and touch 4 and then 3 on the condenser, then 5 to 4 on 5 pin, and then 4 to 2 on the radiator fan. All with the car turned to just the battery on.

Or do you mean connecting the wiring?
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Tuesday, June 7th, 2022 AT 12:30 PM
Tiny
JAKE CURTI
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I figured out what you meant and went out and got copper wire to jump them.
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Tuesday, June 7th, 2022 AT 7:46 PM
Tiny
JAKE CURTI
  • MEMBER
  • 44 POSTS
Nothing when I did this. However, these things are fried. The left one is melted around the prong, here are both connections directly to the fans.
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Wednesday, June 8th, 2022 AT 9:59 AM
Tiny
KASEKENNY
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Yep. That is what I meant. Good job.

So, if that doesn't change anything then the relay is not the issue.

This means we need to check the power at the motor. Which means we would have a connection issue which I suspect you found. Those connectors do not look good.

Checking power will confirm this. Basically, we need to back probe the fans and find out if you are getting 12 volts to them when you should. What I would do is hook up the meter and then start the engine. When it warms up the fan should be on, and you should have voltage. If you have voltage but no fan, then the motor is most likely the issue.

Again, these connections do not look good so I suspect we will find that is an issue.

Before you just replace the connector, I would run 12 volts to the motors and make sure they are able to come on.
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Wednesday, June 8th, 2022 AT 5:02 PM
Tiny
JAKE CURTI
  • MEMBER
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Ironically, I just picked these up 10 minutes ago to hook the fan directly to the battery. These will work, right? I believe the pictures I showed were the receiving connectors to the fan, not the one going from the battery.
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Wednesday, June 8th, 2022 AT 5:15 PM
Tiny
KASEKENNY
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Those are perfect. I would then use what is called a T pin and back probe the connector and then just clip those to the T pin (safety pin).

Or if you can take the connector off and those will clip to the terminals of the fan but those will make it much easier.

Correct. Those pictures of the terminals that did not look good appears to be of the ones off the fan.
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Wednesday, June 8th, 2022 AT 6:35 PM
Tiny
JAKE CURTI
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So, stick the pins in there and then attach the wires?
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Wednesday, June 8th, 2022 AT 8:20 PM
Tiny
JAKE CURTI
  • MEMBER
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Both fans work perfectly when attached directly! So even though the motor connection itself looks fried, it’s actually the connector that goes from battery to fan that is causing all of the issues.

So, would I just splice and connect a new connector for both? The connector that attaches to the motor itself is actually working, and it’s welded onto the metal.
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Thursday, June 9th, 2022 AT 9:17 AM
Tiny
KASEKENNY
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That is great. You may end up needing to replace the fans anyway. I would suggest you start with the connectors because that has to be corrected.

However, if the new connector does not make a good connection with the motor connection, then that will require the motor to be replaced even though it works. Unfortunately, those connectors on the motor itself cannot be replaced.

Here is a guide that will show exactly how to change the connector:

https://www.youtube.com/watch?v=PxA5wczsCVo

I would start with the connector and if that does not work then unfortunately the motor would be next.
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Thursday, June 9th, 2022 AT 12:23 PM
Tiny
JAKE CURTI
  • MEMBER
  • 44 POSTS
If I do need to replace the motors, is this pretty straightforward that I would be able to do myself?
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Thursday, June 9th, 2022 AT 12:54 PM

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