Prove out the inputs first , a software or pcm hardware concern would be were I would look only when I had confirmed the ect using a resistor and using live data for reference if the fans still dont actuate but do if the offending pins for pulling in relays at pcm are grounded it only leaves the pcm or software . Ok then use pass thru to check pcm calibration level .
Prove the ect then speculate.
Even the so called
I'm also lead to believe that it could have a software conflict!
For a cooling fan on a 10 year old car !!! ???
What is your data source for this ?
I can see the benefit of an update, I wouldn't be applying it to the car though !
Is this another hypothetical example ?
Back in the 1980's when I completed a course on electronics and microprocessors, we completed mapping, we did a module or two regarding software, and yes we also covered CAN and the nodes, the gateways, the data signals sent and received along with sensor and actuator fundamentals etc. yes I would believe a car as young as 10 years could have a software program in it that might be corrupt!
What do you see when back probed at the 2 ECU pins that pull the relays in as you activate stage 1 and 2 Cooling fan ?
Measured with a scope from ignition off > ignition on > fan 1 activated >fan 2 activated looking for any activity even if it is mVolts ??
Any master tech worth his salt will tell you to prove the inputs here first certainly before updating anything . The ect input will be the pcms focus for triggering the relays so just input a false reading to the ecm via a resistor as monitor the pcm output to relay thus proving everything back from the ect!!.
Think simple over thinking will just add confusion to the mix .
Danny
Try to perform first the active tests on cooling system,check the wiring betwwen ECU and the fan relays.
An older version of software will block the cooling of engine?A corrupted software of ECU will leave to update your software or will give you a useless piece of hardware and a lot of headache to replace a bricked ECU?
Best regards