A busted car fan can result to overheated engine and can destroy the water pump. Know how to troubleshoot a car fan that doesn’t function. If you know the basics on electricity and electrical circuits, this will be simple. It won’t take long for you to know the source and manually fix that malfunctioning fan.

1. Inspect for split wires or untied connectors along the fan circuit. Check connectors at the fan motor, relay, sensor or heat sensitive switch, and your car’s computer control system, the Electronic Control Module (ECM). Also, don’t overlook testing for a possible blown fan fuse. These are usual and ignored problematic parts that may trigger a fan’s breakdown.
2. Warm the engine up. Use a voltage test light to test for power to the motor fan with the engine running. If voltage reaches the fan motor, the test light must glow.
3. Stop the engine after seeing the light glow. Apply direct voltage to the fan motor from your car battery utilizing a pair of spare wires. If the fan refuses to work, change the fan motor. If the motor functions, the motor connector is the problem.
4. Find the heat-receptive toggle or heating sensor. If the fan motor starts with direct voltage and the test light did not glow, locate the sensor in the radiator, engine block, or thermostat housing.
5. Gauge the resistance across the heating sensor using a multimeter. With engine shut down and at cool temperature, infinite resistance is revealed; with the engine deactivated and at warm temperature, low resistance registers. If both readings display infinite resistance, that’s instigated fan malfunction. Set a new heating sensor up.
6. Assess the performance of the fan relay if the heating sensor is conveying variable resistance. The power and ground wires are definitely detailed in your service manual based on color codes and the right testing method. If the fan relay doesn’t pass the test, switch it with a new one.
7. Inspect the connections toward the ECM subsequent to seeing if fan relay is running appropriately. If you see open-ended wires or unfastened connectors, do the essential fixes. If you believe an ECM is faulty, bring your car to a service center for a computer analysis. In nearly every circumstance, the ECM isn’t the usual origin of a failing fan problem. The aforementioned steps will confirm your suspicions on what may have been the cause and help you with the solution.