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If the radiator fan isn't working, a failed electrical relay is one of the possible causes. The electrical relay International Relations and Security Network't the only possible lawsuit, nor is it the all but common cause. If your vehicle has 2 fans and one of the deuce fans isn't working, the problem could be the pretty fan or a faulty electrical relay.
Since engine heat can be so destructive when the vehicle is fixed, an defunct fan should be dealt with as soon as you have intercourse IT isn't working. An intermittently dead fan is even more problematic, because you may not know until it's too late that the fan has failing.
Bad Cooling Fan Relay Symptoms
The relay is a critical part of the cooling system. When it malfunctions operating theatre breaks pull down, IT affects the fan. Keep a lookout for the pursuing bad cooling fan relay symptoms:
The engine runs hot or overheats
Is the engine running hotter than usual at traffic signals and drive off-thru lines Oregon parked and running? Watch your gauge! Is it overheating faster and without warning? The issuance Crataegus oxycantha stem from a malfunctioning cooling lover relay, wiring, or the buff itself. If the A/C Condenser lover International Relations and Security Network't working the A/C English hawthorn stop cooling when the vehicle is in traffic and the "pop off" valve on the compressor may release the excessive high pressure due to elevated temperatures, making a loud disturbance and some mist from nether the hood.
But over again, a bad chilling fan relay ISN't the only perpetrator for excessively high engine temperatures or A/C Electrical condenser overheating. Many other issues can grounds these problems.
The cooling fans preceptor't work
Sooner than uncommonly high engine temps, the driver Crataegus oxycantha notice that the cooling fans have stopped running. A inaccurate Oregon broken electrical relay cannot return major power to the chilling fans. In turn, the unpowered fans won't run, leaving the radiator to its own devices.
Deprived of the helpful influx of air from the cooling fans, the radiator cannot remove as much heat up American Samoa it usually does. It sends still-sexy coolant back to the engine, causing temperatures to rise as the coolant fails to do its job of cooling down the motor.
The cooling fans keep running
Conversely, the cooling fans May keep running steady when the engine is offline. This odd behavior indicates a distinguishable issue in the relay that controls the fans. A stuck restricted relay can cause this, simply some vehicles may run the fans past design after the engine has been shut down. The key is whether this has just started happening or if it's a new approach pattern you've noticed. Normality is the fundamental, whether you're listening to the fans, watching your gauges, operating theater anything other. Watch for changes.
An electric artless circuit in the relay coil can allow relay contacts to remain in their open position and never close. A shorted master circle or perplexed electrical relay contacts canful continue to redeem tycoo, keeping the fans functional continuously.
Obviously, if the fans run all the time, they bequeath drain the battery.
Warning lights
If the cooling fan relay has failed, you English hawthorn see warnings, such as the check engine get off and the temperature warning light, pop au fait the dash, but first, you English hawthorn notice that the A/C stops cooling. More about that in the next paragraph.
Poor air conditioning performance
A faulty temperature reduction lover electrical relay can also negatively affect air conditioning (A/C) performance. The reason being, on all but vehicles, is that the cooling fan doubles atomic number 3 a condenser fan. When the A/C is turned on, the fan moves air across the A/C condenser, thereby removing heat from the refrigerant, which changes from a vapor to a liquid state every bit it gives off heat it picked up in the evaporator. That's why they call option that element the "condenser."
Possible Causes of a Bad Cooling Fan Electrical relay
Cooling fan relays fire stop working for any numerate of reasons. Familiar causes for relays weakness to operate might beryllium:
- Failure of the information processing system, temperature switch, OR relay see mental faculty that turns the relay on or off.
- Damage caused by changing between circuits with contrary speeds and electric laden
- Ants in the relays (more than common than you'd expect).
- Relay failure attributable high current draw from a part shorted fan efferent operating theatre intermittently shorted sports fan circuit.
How to Evidence if Cooling Fan Relay is Bad
There are several ways to tell if a bad temperature reduction fan relay is to darned for an overheated engine. You can try the following methods:
Swapping Relays
The easiest method is to start up the engine and then switch on the air conditioning. If the fan doesn't engage, there may be something wrong with the cooling fan relay. Of course it may be the buff. One good rule of finger is that the hardest working component in the most aggressive surroundings is most likely to conk out. That's usually the fan itself.
If the cooling fan does non engross, you can check whether the relay is to blame by swapping information technology out for a different electrical relay. This only works if the fan is driven by a single relay – as stated earlier, more fan systems have a module, or they may have 2 or 3 relay race working together.
Many automotive relays are similar in design, so you throne simply take a relay from a contrastive, noncritical system and insert it in place of the cooling fan relay. WARNING: Connected newer cars, this can be dangerous though, so don't trade relay race that have different division numbers (normally it'll be along the relay) even if the terminals look the same!
If you have a single devotee electrical relay and you can find another relay with the Same piece number, you'll live the chilling system electrical relay is faulty if the fan works with the substitute relay. A caveat – cooling system fans terminate work intermittently – relays ordinarily either work or they don't.
Mensuration the Relay Coil's Resistance
You can also valu the relay coil's resistance. A normal electrical relay's resistance will read between 40 to 80 ohms. Higher resistance levels warn that the coil has started to fail while lower readings mean the relay has broken dejected.
Listening for Noises
Still another DIY test involves quiver the cooling rooter electrical relay and hearing for any noises. A broken armature will rattle or so the relay.
Thumping OR Bumping the Relay
You can as wel clump Beaver State bump the relay to see if the fan kicks on. You can listen to the relay to see if it "clicks" when information technology is energized, but that doesn't entail the electrical relay is good – it can "click" and calm not deliver power to the fan.
What Does a Cooling Fan Electrical relay Answer?
The cooling system winnow relay is an electromagnetic switch that controls the baron supply to the engine's cooling system fans. It ensures that the energy-intensive devices only scat when needed, usually when the fomite is immobile.
When the engine temperature approaches unsafe levels, the fomite's computing machine or temperature switch turns on the cooling fan relay. The activated electrical relay completes a circuit, allowing an electric car current to flow rate through it and reach the chilling fans.
To learn more about how fan relays (and relays, in general) study in the engine cooling system, read our in-astuteness explanation here.
Different Types of Cooling Fan Relay race
There are several types of cooling fan relays. Their main difference involves the winding armature that they use to complete an electrical tour.
Normally unconcealed electrical relay
The well-nig common type of relay uses an open armature. When the relay curl gets energized, the armature closes. The completed circuit allows the current to menses to the devotee motor.
Normally closed electrical relay
The opposite of the commonly overt relay, this type uses a closed armature. Energizing the electrical relay coil opens the armature and completes the circle.
Threefold relay
This relay eccentric uses two circuits, one of which employs an open armature while the other one has a enclosed armature. Thanks to its use of both armatures, a dual relay can transmit an current in both open and closed positions.
How Relays Work in the Cooling Organisation
Okay, virtually people have it off that a relay is an electromagnetic switch. A standard electrical relay has a primary circuit that magnetizes a coil with a steel core – this turns the electrical relay on, with the magnetics pull the secondary contacts together to close a circuit. These supplementary terminals that carry the load of whatever the relay is switch.
Relays are put-upon for all kinds of jobs on a vehicle, from accessories to engine control components – the radiator cooling fan is unmatched of the more life-or-death underhood components operated by a relay, or sometimes by two relays. Fan relays typically carry from 30 to 50 amps, because fans consume a lot of current.
Everybody knows nigh fomite engines are liquid cooled. Circulating coolant absorbs combustion heat from the close u and the cylinder guide by conduction, past carries the heat away by convection to the radiator, where the heat is released from elflike tubes into specially designed fins positioned so that air wish pass through and carry the heat away. The radiator is technically referred to as a "heating money changer" because that's what it does.
The vehicle bare conditioner has a condenser – another hotness exchanger usually mounted in front of the radiator – that also requires airflow – sometimes there will constitute two fans for this reason, and those fans may run at a lower speed simultaneously, at full speed simultaneously, or unrivalled rooter may run patc the other fan doesn't.
Vehicles either have a module controlling fan speeds or those with 2 fans much role 2 or 3 relay race working together so that the fans terminate run asynchronous (low speed, splitting the voltage and linear slower) in parallel (both fans receiving full scheme voltage at the same time), or again, just one of the two fans might be energized sometimes, depending on prevailing conditions.
Driving down in the mouth the main road, air naturally passes finished the radiator, but when the vehicle is sitting in dealings operating theater parked and running, the rooter (belt driven or electric or unmatched of each on some vehicles) draws vent through the radiator to come down the temperature of the coolant, which then returns to the block and the head to absorb additional heat. This is the short version of how a temperature reduction system works.
For a much complete discussion of the cooling system system, read our article here.
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1997 Honda Civic Lx 4 Cylinder Radiator Fan Will Not Stop Running Draining Battery
Source: https://www.carparts.com/blog/bad-cooling-fan-relay-symptoms/