Cooling Fan, Overheating

[rzc]

My apologies for the lengthy post, but I want to provide the full picture so I can get some proper guidance from the experts here.

Two days ago, I noticed that my A/C wasn’t cooling well when idling — it only worked properly when the car was moving. I brushed it off since it was intermittent during my 70+ mile commute home.

Yesterday, the same thing happened, but this time it was while I was in stop-and-go traffic on the interstate. At first, the coolant temperature gauge looked normal (around the halfway point). A few minutes later, I got a warning about overheating, and I saw the temp gauge rising. I pulled over and called AAA.

Here’s what I found:

The F43 (30A) cooling fan fuse was blown.

I replaced it, but it blew again as soon as I turned on the A/C.

After some online research, I did a bit of troubleshooting:

Removed the airbox and disconnected the cooling fan power.

Replaced the fuse and started the car — it held.

Turned on the A/C — the fuse still held.

This points to the cooling fan or relay being the culprit.

I tested the fan connector and found continuity between all three legs, which I believe is normal. No open circuit.

My coolant level is fine, and I also checked the oil dipstick (no signs of milky residue). For context, my car is a 2023 CX-30 with 51k miles, and I do operate in a harsh environment with frequent sand exposure from the beaches.

My questions:

Does this sound like a failed cooling fan (possibly shorted windings)?

Should I go ahead and replace the fan assembly, or is there something else I might be missing? I was able to determine and test the relay, that was good.

Lastly, does anyone have any documentation on replacing the fan?

Any advice or shared experiences would be much appreciated.

Thanks in advance!

Below are pics for reference:

This is where the fuse is located. The larger square relay is the bosch type relay for the cooling fan.




These are the 3 legs of the power to the cooling fan.

 

[N7turbo]

Props to doing the diagnostics, but my first thought is that this is under warranty so if you do need a new fan, you shouldn't pay for it.

 

[rzc]

Props to doing the diagnostics, but my first thought is that this is under warranty so if you do need a new fan, you shouldn't pay for it.

It's not, I'm at 51k miles.

 

[SparkYellow]

Appreciate your sharing the troubleshooting process. You said you tested the relay and it was good, did you mean you swapped it with a different one and it worked for that other function? The relay you marked seems to be of a difference size/spec from all the other ones in the box. Asking so I can learn. Thank you!

 

[rzc]

Appreciate your sharing the troubleshooting process. You said you tested the relay and it was good, did you mean you swapped it with a different one and it worked for that other function? The relay you marked seems to be of a difference size/spec from all the other ones in the box. Asking so I can learn. Thank you!

I used a meter and removed the relay then used a 9volt battery to 85/86. Made sure I can hear the click on/off. Then also confirmed voltage on 30/87. I also tested where the relay goes and tested continuity to where the fuse goes.