I have a little trouble following that. Can you try again in sentences and using real words, stepping us through it in more coherent fashion?

 

the cooling fans are not working.i checked fuses and relays and there working fine.i decided to replace the cooling fan sensor.when i was checking the sensor i unplugged it and the fans came on or turned on.if i plug the sensor back up the cooling fans shut off,could this be faulty sensor or whats the next step to look for,has anyone had a similar problem? the vehicle is a 2007 murano with 75k the cooling fan sensor i replaced was the o.e had Nissan logo stamped and made in japan.

 

Hi, did you ever get to the bottom of this? Our murano also does the same thing and have experienced what you have.

 

Thanks for a clearer story.

This made me wonder if the default state for the fans is ON, in the absence of a sensor. But that wouldn't make sense because if the ignition was off, it would run the battery down if a sensor failed.

Was the ignition on or off when the fans started? I must assume it was on.
I'm gonna have to think on this one. I hope someone has a good idea to get started on.

 

the vehicle was running.when i was checking the sensor.

 

Today i went and bought a code reader.did a scan and i got code p 0118 .looked it up online and said there were several things that can cause this,bad ect, low coolent level,faulty thermostat or bad ect connection.i have replace the sensor thats next to the trany shift linkage is there another sensor i need to replace?

 

Thanks for all the comments and all your help.i wouldn't have done it with out the y'all.

 

I sense a little sarcasm there

 

I just didn't have anything more helpful to say. I don't know the specific system. Such is life.

 

LOL. Maybe we should all start the practice of posting something even when we have no clue? I have seen that happen a few times and believe me it was not pretty....

 

Hey folks
My 07 Murano sl is having a fan problem. If I run the air the fans operate. If I don't run the air they don't work. Any suggestions? Thanks

 

Well, I get the same issue. It cracked the radiator, replaced that and noticed fan was not working. I've changed the coolant sensor and noticed fan was not turning on even after waiting 20 mins and had heater on. I can feel heat coming out of the vents inside the car. Also noticed when I unplug the harness connected to the collant sensor, then radiator fan turns on immediately.

 

Also noticed when I unplug the harness connected to the coolant sensor, then radiator fan turns on immediately.

This is fail-safe mode when the ECM isn't getting a signal from the ECT sensor. The ECM controls cooling fan operation, but the IPDM actually turns the fans on/off via the relays. The fact that unplugging the ECT sensor causes the fans to come on means the ECM can receive a signal (or lack thereof) from the ECT sensor and the IPDM can turn the fans on when commanded. Below is a graphic that shows the conditions for when the ECM will command the fans on.

Are you using a scan tool to monitor actual coolant temperatures as reported by the sensor? You want to be sure the reported temperature is rational. Do the cooling fans turn on when you turn the A/C on?

BTW, did you make sure to bleed the cooling system well after replacing the radiator? Pockets of air in the cooling system will affect the ECT sensor reading.

 

Thank you for the explanation. I tried my best to bleed out the cooling system but its possible ther e maybe trapped air. I left the radiator cap open with funnel filled with coolant and let the car run on idle for a good 20 mins with heater on and I can feel hot air coming out of the vents and no more bubbles on funnel.
The fans don't turn on when I turn on the aircon, do you know what could be wrong here?

 

The fans don't turn on when I turn on the aircon, do you know what could be wrong here?

Run the IPDM Auto Active Test detailed in the PDF attachment. Do both of the cooling fans turn on at low and high speeds?

 

Run the IPDM Auto Active Test detailed in the PDF attachment. Do both of the cooling fans turn on at low and high speeds?

Hi, sorry it took me a while to respond as I was away and could not run this test. I ran it today as soon as I came back and the fans DO turn on on both high and low speeds.

 

The fans don't turn on when I turn on the aircon, do you know what could be wrong here?

Does the A/C blow cold? When the A/C is on the coldest temperature setting, can you see the A/C clutch turning with the pulley to confirm the compressor is running?

I ran it today as soon as I came back and the fans DO turn on on both high and low speeds.

This is good in that you at least know the fans can turn on. What year is your Murano?

Do you have a scan tool capable of reading live data?