High Speed Engine Cooling Fan Relay

The engine cooling fan only runs when needed to help cool the engine.

High speed engine cooling fan relay.

Mechanical fans can sometimes work better than electric fans. It basically runs two fans in series for low speed and then put s each on it s own 12v circuit for high speed. The fan runs mostly at idle or low speed when the engine is at normal temperature. The relay controls when the fan turns on and off based on coolant temperature.

The relay will usually be activated once it is detected that the vehicle s temperature approaches excessively high temperatures. It is a bit confusing till you understand what is going on. The function of the cooling fan relay is to convert a low voltage signal from either the electronic control module ecm or a thermostatically controlled sensor. Related engine cooling fan diagnostic codes.

When the correct parameters are met a temperature switch or the computer will activate the relay which will allow power. In the 2012 the relay was relocated next to the master cylinder along the driver side of the engine bay. The new relay setup is a dual relay and i found the one that i needed to replace was on the left of the two closest to the cab. While monitoring the cooling fan the ecm detected a high speed condition.

So a engine cooling fan failure. Usually use a cooling fan. When the fan is on too often or won t come on at all a new relay may be the solution. Most fans should come on when the coolant reaches about 200 to 230 degrees.

If the cooling fan is spinning beyond or below the manufacturers set parameters the engine light or malfunction indicator lamp mil will be illuminated by the ecm. I hope this video will. A larger radiator a larger clutch fan and a shroud would probably keep your engine cool. Or a failure of the fan relay or control circuit.

In the 07 12 model the high speed relay was behind the driver side headlight. Using a mechanical fan for a high horsepower application can work just fine if a couple of things are considered. The cooling fan relay takes the low voltage signal and internally switches the relay â œonâ to allow battery voltage to be supplied to the radiator cooling fan. If your cooling fan runs all the time or not at all or if your engine runs hot it might be time to replace your cooling fan motor or relay.