I've seen quite a few galvanic cooling fans give up the ghost recently. The complaint from the driver is normally the air conditioning is not working. Although some owners may notice a car overheating condition. In whether case, one of the first things that a mechanic will check is to verify that the galvanic cooling fan is running when it is supposed to be.
The ample efficiency of a car's cooling principles is based on the estimate of heat that can be removed from the cooling principles and transferred to the air around it. At highway speeds ram air straight through the radiator is enough to vocalize proper cooling.
When the engine is idling or the car is at very low speeds. The engine's cooling principles needs supplementary airflow. On contemporary cars an galvanic cooling fan delivers this air.
The use of this type of fan eliminates the power drain while times when fan performance is not needed. Although there are vehicles still man-made with belt driven fans, they are not as productive or used as often as galvanic fan motors.
In most late-model applications galvanic fans save power and sell out the noise level of the vehicle. It's hard to say how long one of these units will last, because it depends on the vehicles operating conditions. Even though contemporary fans are well sealed they are still made with metal parts that can wear and corrode over time.
When I have one of these cooling fan motors to diagnose I will often go right for the source and check for power and a good ground at the motor itself. I have also seen mechanics take their power probe and furnish 12 V to the fan motor to see if it runs. I have also seen and used the tap test where you just use the handle of a screwdriver to tap on the back of the galvanic motor.
Note that a excellent mechanic should show the way these tests. The cooling fan can be a perilous car part. If a fan motor tests good then you will have to check the other side of the circuit. This consists of a cooling fan temperature switch and a fan relay.
The temperature switch could be settled in a few separate places. But often they are mounted near the thermostat. The coolant temperature switch is a simple on or off switch that sends power or ground to the cooling fan relay.
This should not be confused with the coolant temp sensor for the computer, which on many vehicles is separate. When the engine coolant is below 230° or so. The switch will remain open and the fan will not run. When the temperature switch senses the engine to be over 230° the switch closes. This energizes the coil in the relay, end the contacts and sending 12 V power to the cooling fan motor.
The above is coarse example of a coolant fan motor circuit. Some vehicles may have more complicated systems. Some car makers will even use the ground side of the circuit to control performance of the fan.
galvanic Cooling Fans Cause Car Problems