Hi every one,i have a 2011 Honda CRV 2.4 , i need help with a radiator fan that is not engaging when running hot, things i have done so far,
Replaced the radiator cap,
Presure and chemical test on radiator
Temp sensor replaced
replaced the Thermostat
Changed the Radiator fan relay fuses
both fans working when Aircon is engaged
Is there something that i am missing?

 

There should be two ECT (engine coolant temperature sensors)
And there should be three relays that control the fans (ac fan, fan control, radiator fan)
Four if you count the PGM-FI sub relay.
They either put the fans in series for lo speed
Or they put the fans in parallel for hi speed
With the AC on, that says the fans work and the fuses are okay.

This leaves me scratching my head.
If the ac fan relay is stuck closed then the radiator fan will not turn on but the ac fan would be on
If the radiator fan relay is stuck open then the fan would never turn on but it does when ac is on

Hmm, everything is controlled by the PCM.
And it gets its information from the ECT's

Sorry, doesn't make sense???
If radiator fan is stuck closed then it would be on all the time.