The cooling fan relay is an electromagnetic switch that controls the power supply to the engine’s cooling fans. - The vehicle speed is less than 38 MPH. Open the hood and do a visual inspection. - The A/C clutch requested. Open or shorted fan control relay harness 2. Defective faulty fan control relay 1 2. Poor electrical connections in the cooling fan circuit 6. NOTE: P0480 speaks of the basic circuit, however codes P0481, and P0482 relate to the same problem with the only difference is they relate to the different fan speed relays. See the schematic printed on the relay itself or consult the schematic in your vehicle repair manual, if necessary. A relay kit, our part number CCFKRL, will include everything you need to properly wire up your electric cooling fans, with the exception of additional wiring needed to complete all of the circuits. This is a generic powertrain diagnostic trouble code (DTC), which means it covers all makes/models, 1996-newer. The cooling fan relay coil receives the Ignition Voltage directly. With this sort of an illustrative manual, you’ll have the ability to troubleshoot, avoid, and complete your assignments without difficulty. Eautorepair.net redraws factory wiring diagrams in color and includes the component, splice and ground locations right in their diagrams. You just want to know if it's working. + + this will be your new ground switched output. Check all the relays in the same fashion to be sure they are all working. IAT (intake air temperature) failure 8. If they are good pull the cooling fan relays out. Look at the side of the relay for the switched power terminal or just turn the key on. When you bring the car to a stop no air is passing through the radiator and the engine begins to increase in temperature. In the Painless Performance electric fan relay kit we got from Speedway Motors, a circuit breaker is supplied if you wanted to safely get power directly from the battery. This is a generic powertrain diagnostic trouble code (DTC) applicable to most 1996-newer vehicles. Defective coolant temperature sensor 7. A switched terminal will be hot only when the key is on. Electric fan is responsible for causing air movement around the engine coolant radiator. This one turns on the fan when the circuit is closed. Anyone know where the relay for the cooling fan is? When … A duty cycle is determined based on these input parameters. Radiator fan relay switch wiring electric override electrical diagrams how to replace a cooling fan relay on most vehicles 2002 dodge caravan cooling fan relay wiring 2016 grand 2006 ford escape fuse diagrams ricks auto repair. Related. Refer to the top or side of the relay to locate these terminals. If they prove to be good, check the CTS with an ohmmeter. A/C selector switch 9. DIAGNOSTIC TROUBLE CODE (DTC) - P0481 HIGH SPEED COOLING FAN RELAY CIRCUIT FAULT (WITHOUT A/C) Details of the Circuit. If not, disconnect the fan connection at the fan and using an ohmmeter check the continuity between the fan side of the relay terminal and the connector at the fan, If there is continuity the fan is bad. Video on how to diagnose dtc p1491, radiator fan control relay circuit malfunction on a 2003 jeep liberty sport. The fan relays are nothing but a remote light switch. Use a test light to find the hot terminal. The cooling fan relay is the relay that controls the engine’s cooling fans. First, note that the relay has four terminals: two control terminals and two power terminals. Most late model vehicles use an electric fan to pull air through the radiator. Some Dodge vehicles have a solid state radiator fan controller that varies the fan speeds by pulsing the ground to the radiator fan motor. Pricing: ---Eautorepair.net--- 1 month subscription $19.95 per vehicle 1-year subscription $29.95 per vehicle 4-year subscription $44.95 per vehicle ---Alldatadiy.com--- 1-year $29.95 subscription: additional vehicles $19/95 each 5-year $49.95 subscription: additional vehicles $34.95 each Which one should YOU choose? A/C refrigerant pressure sensor 10. Step 1 - A relay is used to control (switch) a high amperage electrical circuit with a low amperage one, for example a radiator fan can pull up to 25 amps when in use, which would burn the computer circuit that controls it, a relay is used to bridge this circuit to prevent electrical damage. If necessary, a replacement relay costs around $20.There are three ways to check for a bad terminal. When the PCM attempts to activate the fan and senses the command and the result do not match, the code is set. However, Alldatadiy.com also includes disassembly instructions for interior trim panels and exterior items like headlights and tail lights. Get the BEST auto repair information Alldatadiy.com and Eautorepair.net are professional-grade shop manuals—period. A/C refrigerant pressure sensor 10. If swapping relays still doesn't operate your cooling fan, make sure the relay is receiving power from the computer. Most late model vehicles use an electric fan to pull air through the radiator. All content © 2004-2021 OBD-Codes.com, Cooling fan 2005 Chevy Tahoe 5.3L p0480 [Solved], 2000 Olds Silhouette p0131, p0137, p0480, p0742 + more, 2005 Chevy Trailblazer Ext P0480 wont start, post Faulty cooling fan 1 3. Cooling Fan 3 Relay Control Circuit High. Contact Us If you’re tracking down a wiring issue, Eautorepair.net is the better choice. Specific repair steps can vary from make/model. A code P1492 indicates a problem with the relay circuit. (adsbygoogle = window.adsbygoogle || []).push({}); While you are driving, air in sufficient quantity is passing through the radiator effectively cooling the engine. IAT (intake air temperature) failure 8. Use an ohmmeter to test that the constant battery terminal and the fan harness terminal have continuity meaning the circuit has closed. It is a generic code applying to all OBD II (on board diagnostics) vehicles. If you need to dig into your doors, dash or console, Alldatadiy.com is the better choice because Eautorepair.net doesn’t any interior or exterior trim or body part removal. If you still need help regarding the P0480 trouble code, please post Pull the connector apart and look for corrosion or bent pins. Until such time as you can either complete your checks of the circuits or take the car to a service facility, pull the fuse in the fuse relay … Mount the fan as high up on the core as possible. The PCM (powertrain control module) senses the increase in engine temperature through the CTS (coolant temperature sensor) located near the thermostat. Verify the battery positive terminal in the relay block with constant power. Let the engine cool and put the ohmmeter on the 200,000 scale. The amount of air movement caused by the fan is controlled based on the Vehicle Speed, coolant temperature, A/C pressure status, A/C switch request status, and A/C clutch state. Alldatadiy.com, on the other hand, uses the factory diagrams. Faulty VSS (vehicle speed sensor) The vehicle computer monitors coolant temperature with a sensor located near the thermostat. The cooling fan relay takes the low voltage signal and internally switches the relay “on” to allow battery voltage to be supplied to the radiator cooling fan. Most cooling fans use electric motors that have a moderate to high current draw, and as a result are commonly controlled using relays. Defective or faulty fan control relay 3 4. - The vehicle speed is less than 38 MPH. If the fan operated, check the relays. If the above procedure could not find a failure, the probability is that a poor connection to the PCM or the PCM itself is at fault. Look at the circuit diagram displayed on the side of the relay. This tutorial will help you to diagnose the Pulse Width Modulated (PWM) fan relay on the 1999-2003 Jeep 4.0L Grand Cherokee SUVs and/or the codes P1491 (Radiator Fan Control Relay Circuit).The dealer, at the time of this writing, will charge you $95 (US) to diagnose it. Set the … Spin the fan with your finger (make sure the vehicle and key is off). Poor electrical connections in the cooling fan circuit 6. Some of the most common possible causes are: 1. While you are driving, air in sufficient quantity is passing through the radiator effectively cooling the engine. The schematic will help you also when checking the fan cooling circuit. Pull the connector off. The PCM controls the cooling fan by grounding the cooling fan control circuit which turns ON the cooling fan relay. The cooling fan relay will be commanded ON when the following conditions are met: - The engine coolant temperature reaches 106°C (223°F) or more. Shut the engine down and pull the CTS plug again. A constant power supply from the battery is present on a terminal in each of the relays. It is not intended as repair advice and we are not responsible for any actions When the temperature reaches about 223-degrees F (value depends on make/model/engine), the PCM will command the cooling fan relay to turn on the fan. Check the terminals for an additional power terminal and look where it would be on the relay. The activated relay completes a circuit, allowing an electric current to flow through it and reach the cooling fans. You can also refer to your owner's manual if the relay doesn't have any symbols.Resistance Test: 1. Additionally, many vehicles have multi-speed fans requiring as many as three fan speed relays for low, medium and high. cooling fan relay wiring diagram – You will need a comprehensive, expert, and easy to understand Wiring Diagram. This is a generic powertrain diagnostic trouble code (DTC), which means it covers all makes/models, 1996-newer. If you have a P1491 Radiator Fan Control Relay Circuit trouble code, this post will help you understand what it is and how to fix it. Multiple factors can lead to this error code, some of the most common possible causes are: 1. The relay is regulated by grounding the control circuit via the driver or the internal switch, a process which is entirely controlled by the ECM. What does that mean? The cooling fan relay will be commanded ON when the following conditions are met: - The engine coolant temperature reaches 106°C (223°F) or more. Disconnecting the PCM could cause loss of programming and the vehicle may not start unless towed to the dealer for reprogramming. They include wiring diagrams and technical service bulletins. The bottom of the fuse block lid will usually indicate placement, but if not, look in the owner's manual. If there was no switched power at the relay, the ignition switch is suspect. A/C selector switch 9. Do not go any farther without consulting your service manual. In most cases, their diagrams are right from the factory manuals. There must be a relay that the control circuit closes, this relay may be welded closed or the control circuit is telling the cooling fan to run. But other Chrysler and Dodge vehicles use a more traditional radiator fan relay. - The A/C clutch requested. Open or shorted fan cooling fan harness 3. However, specific troubleshooting steps will vary depending on the vehicle. Look for the simple open and shut circuit. The fan that is not in front of the air conditioning condenser is the main cooling fan and the one to concentrate on initially. However, specific troubleshooting steps will vary depending on the vehicle. Look at the markings on top or side of the relay case and locate the two control circuit terminals, which connect to the relay's coil, and the two power circuit terminals, which let electrical current pass to the fan. C5 corvette electric fan relay wiring to wire an electric fan with a relay arduino controls fan tutorial trinary switch infinitybox 12v toggle switch wiring… Best Fan In Thestylishnomad.Com 13560+ Best Fan Thestylishnomad.Com 2019 It is a generic code applying to all OBD II (on board diagnostics) vehicles. your question in our FREE car repair forums, Check engine light (malfunction indicator lamp) illumination and code P0480 set, Engine temperature will rise when the vehicle stops and idles, Fan control relay harness is open or shorted, Fan cooling fan harness is open or shorted, Cooling fan circuit poor electrical connection. This will allow mounting of the fan(s) without compromising the core of the radiator. (Please call for fan shroud suggestions). If your vehicle's check engine light comes on and after pulling the code you find a P0480 displayed, if refers to the engine cooling fan circuit. Accuracy isn't necessary since all sensors may be different. The fans that are used to cool the engines radiator are run by electric motors. There are multiple factors that can lead to this error code. Check the electrical connection at the fan. All information on this site is copyright protected. ground switched device using a simple spst relay. NOTE: This information is presented for information purposes only. Cool Automotive Products and Tool Recommendations, Read AUTO REPAIR ARTICLES sorted by topic, Generic non-manufacturer-specific P code definitions, Honda alternator and charging systems explained, Harsh shift, rough idle, GM service bulletin #PIP5446A, Custom Wordpress Website created by Wizzy Wig Web Design, Minneapolis MN. Faulty cooling fan 3 5. So you have to refer to the factory legends to learn the identification symbols and then refer back to circuit diagrams to find the splice and ground locations. The PCM controls the cooling fan by grounding the cooling fan control circuit which turns ON the cooling fan relay. Jump the battery plus terminal in the first test with this switched terminal and place an additional jumper from the negative terminal on the relay to ground. Most modern vehicles use electric cooling fans to help pull air through the radiator so that it can keep the engine cool. If your vehicle's check engine light comes on and after pulling the code you find a P0480 displayed, if refers to the engine cooling fan circuit. Defective coolant temperature sensor 7. Open or shorted fan control relay harness 4. your question in our FREE car repair forums. Open or shorted fan cooling fan harness 5. Reconnect it and warm the engine. There is a problem within this circuit causing the fan to fail to operate allowing the engine to overheat while sitting still or driving at a slow speed. If you have a P1491 Radiator Fan Control Relay Circuit trouble code, this post will help you understand what it is and how to fix it. The vehicle's PCM's function is to act as a ground to operate components, not to supply power. The switch will click on. The reading will be about 2.5. adjustable fan switch/thermostat with built-in relay and radiator probe (12v switching, non-variable speed only) 86 30 87 85 5 amp fuse signal circuit 12v switched (ignition or fuse panel) power “on” when key is in the “run” position. Many vehicles will have two engine fans, one for engine cooling and the second for cooling the air conditioning condenser, and additional cooling for the engine. Look at the fan and make sure there is no obstruction in front of the radiator blocking airflow. Repair if necessary and use dielectric grease on the terminals. The operating components in the cooling fan circuit include the cooling fan fuse, relay, coolant temperature sensor and the computer. - The A/C clutch requested. Published by Saum Hadi. The fan as well as other apparatus draws too much amperage to be safe in the cockpit, so it's kept under the hood. Jump the battery terminal to the fan harness terminal and the fan will operate. The ground completes the circuit to the relay and switches power to the fan. The opposite side goes to the fan. P1491 Radiator Fan Control Relay Circuit P1491 Radiator Fan Control Relay Circuit. Check it with the ohmmeter, there should be a big change in resistance, if not the sensor is bad. Search using your favorite search engine "technical service bulletins for ....." Look up the code and the type of manufacturer recommended repair. How Dodge Radiator Fan Wiring Diagram is set up. By using a lower voltage signal to control the relay, there is less stress on the rest of the wiring and charging system. Faulty VSS (vehicle speed sensor) That saves a lot of time because you don’t have to refer back to the component locator or circuit locations. Dodge Radiator Fan Wiring Diagram. The cooling fan relay will be commanded ON when the following conditions are met: - The engine coolant temperature reaches 106°C (223°F) or more. Recently, I was driving my 2015 Jeep Wrangler JK Unlimited through a parking lot on a 95 degree day, and after leaving a stop sign, a check engine light flashed on (later I would learn it was a P0480 Cooling Fan Relay 1 Control Circuit), and shortly thereafter my Jeep overheated. It is always a wise idea to look up the technical service bulletins (TSB) on your particular vehicle to see what type complaints have been coming in to the dealer service department related to this code. This is also a good idea before buying a vehicle. Probe the sensor terminals. The negative terminal in this circuit is the one used when the PCM wishes to active the relay by grounding it. Electric Fan Relay Wiring Diagram– wiring diagram is a simplified tolerable pictorial representation of an electrical circuit.It shows the components of the circuit as simplified shapes, and the capability and signal contacts between the devices. - The vehicle speed is less than 38 MPH. For precise readings consult a service manual. A malfunctioning cooling fan relay can … The PCM controls the cooling fan by grounding the cooling fan control circuit which turns ON the cooling fan relay. Any one know where the thermostat or temp switch for the control circuit is? If not the harness between the fuse block and the fan is faulty. you take on any vehicle. Attach the fan to the small area around the core Of the radiator where there is a metal lip that is approximately 1/4" to 3/8". If it will not spin the fan bearings are shot and the fan is bad. When coolant temperature rises above acceptable limits, the computer provides ground to the fan relay. 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