Cooling fan/condenser fan not operational under normal conditions (car is turned on, neither fan engages under any circumstance). As follows:
• Power applied directly to either fan from battery with alligator clips causes either fan to spin. • Fuses functioning (test light confirmation) #2, #39, #8. • Cooling fan relay disconnected, jumped terminal #2 and #4 with paperclip, cooling fan operates (whether the car is on or not). • No voltage present between terminals #1 and #3 with car in on position and A/C on. • Applying ground to terminal #1 causes the condenser fan to engage and spin. • 5.03v deteced on ECT sensor A (closest to firewall, next to thermostat). • 12.28v detected on ECT sensor B (closest to bumper, next to upper hose). • Jumping ECT sensor A with paperclip (near thermostat) yields no result, car on or off. • Jumping ECT sensor B with paperclip (near bumper) engages cooling fan only after the car is turned off.
Thank you for your assistance.
My car has 230000 miles.
My car has an automatic transmission.
Hi there. Your issue is the ECT sensor B is not closing the loop when engaged. There is power to the sensor A from the computer, but the sensor B is not connecting when the vehicle is running hot or when the air conditioning is on. I recommend replacing the ECT sensor B, which is the on and off switch for the cooling fans. On the relay, terminals 2 and 4 are the direct circuit for the cooling fan, terminal 1 is the ground, and terminal 3 is for the circuit to the air conditioning system. Check the wiring between the fuse box and the terminal 3 for resistance and see if there is 0.5 ohms or less. If the meter reads OL, then there is a break in the wires and it would need fixed or replaced. If there is 0.5 ohms of resistance or less, then check the A/C switch and the ignition switch as they could be the source of disconnection. If you need further assistance with your cooling fans not working, then seek out a professional, such as one from Your Mechanic, to help you.
Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing