Let the engine cool and put the ohmmeter on the 200,000 scale. Any one know where the thermostat or temp switch for the control circuit is? - The A/C clutch requested. 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 cooling fan relay will be commanded ON when the following conditions are met: - The engine coolant temperature reaches 106°C (223°F) or more. If swapping relays still doesn't operate your cooling fan, make sure the relay is receiving power from the computer. Search using your favorite search engine "technical service bulletins for ....." Look up the code and the type of manufacturer recommended repair. The fan as well as other apparatus draws too much amperage to be safe in the cockpit, so it's kept under the hood. Pull the connector apart and look for corrosion or bent pins. A constant power supply from the battery is present on a terminal in each of the relays. 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. The ground completes the circuit to the relay and switches power to the fan. 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. 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. How Dodge Radiator Fan Wiring Diagram is set up. NOTE: This information is presented for information purposes only. If they prove to be good, check the CTS with an ohmmeter. cooling fan relay wiring diagram – You will need a comprehensive, expert, and easy to understand Wiring Diagram. Eautorepair.net redraws factory wiring diagrams in color and includes the component, splice and ground locations right in their diagrams. 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 side of the relay for the switched power terminal or just turn the key on. A/C selector switch 9. While you are driving, air in sufficient quantity is passing through the radiator effectively cooling the engine. When coolant temperature rises above acceptable limits, the computer provides ground to the fan relay. Check all the relays in the same fashion to be sure they are all working. Alldatadiy.com, on the other hand, uses the factory diagrams. (adsbygoogle = window.adsbygoogle || []).push({}); While you are driving, air in sufficient quantity is passing through the radiator effectively cooling the engine. Open or shorted fan cooling fan harness 5. The vehicle computer monitors coolant temperature with a sensor located near the thermostat. 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. 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 Defective coolant temperature sensor 7. Open or shorted fan control relay harness 4. For precise readings consult a service manual. 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. What does that mean? you take on any vehicle. You just want to know if it's working. A code P1492 indicates a problem with the relay circuit. Disconnecting the PCM could cause loss of programming and the vehicle may not start unless towed to the dealer for reprogramming. A malfunctioning cooling fan relay can … If there was no switched power at the relay, the ignition switch is suspect. 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 cooling fan relay will be commanded ON when the following conditions are met: - The engine coolant temperature reaches 106°C (223°F) or more. The PCM controls the cooling fan by grounding the cooling fan control circuit which turns ON the cooling fan relay. - The vehicle speed is less than 38 MPH. Defective coolant temperature sensor 7. The cooling fan relay is the relay that controls the engine’s cooling fans. 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. Additionally, many vehicles have multi-speed fans requiring as many as three fan speed relays for low, medium and high. - The A/C clutch requested. They include wiring diagrams and technical service bulletins. This is a generic powertrain diagnostic trouble code (DTC), which means it covers all makes/models, 1996-newer. Pull the connector off. - The A/C clutch requested. 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. With this sort of an illustrative manual, you’ll have the ability to troubleshoot, avoid, and complete your assignments without difficulty. Verify the battery positive terminal in the relay block with constant power. The fans that are used to cool the engines radiator are run by electric motors. Electric fan is responsible for causing air movement around the engine coolant radiator. A switched terminal will be hot only when the key is on. When the PCM attempts to activate the fan and senses the command and the result do not match, the code is set. But other Chrysler and Dodge vehicles use a more traditional radiator fan relay. Faulty VSS (vehicle speed sensor) 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 The operating components in the cooling fan circuit include the cooling fan fuse, relay, coolant temperature sensor and the computer. Faulty VSS (vehicle speed sensor) The switch will click on. If the circuit has not closed or the relay has not clicked, the relay is bad. Mount the fan as high up on the core as possible. 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. 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. The PCM controls the cooling fan by grounding the cooling fan control circuit which turns ON the cooling fan relay. The vehicle's PCM's function is to act as a ground to operate components, not to supply power. Jump the battery terminal to the fan harness terminal and the fan will operate. Published by Saum Hadi. If the fan operated, check the relays. Probe the sensor terminals. 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. Use a test light to find the hot terminal. 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 … The activated relay completes a circuit, allowing an electric current to flow through it and reach the cooling fans. Check the terminals for an additional power terminal and look where it would be on the relay. A/C refrigerant pressure sensor 10. This one turns on the fan when the circuit is closed. + + this will be your new ground switched output. Shut the engine down and pull the CTS plug again. 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. 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. Poor electrical connections in the cooling fan circuit 6. Check it with the ohmmeter, there should be a big change in resistance, if not the sensor is bad. It is a generic code applying to all OBD II (on board diagnostics) vehicles. It is a generic code applying to all OBD II (on board diagnostics) vehicles. The radiator fan switch relay may not be supplying power to the fan. Specific repair steps can vary from make/model. The opposite side goes to the fan. (Please call for fan shroud suggestions). Look for the simple open and shut circuit. Look at the fan and make sure there is no obstruction in front of the radiator blocking airflow. By using a lower voltage signal to control the relay, there is less stress on the rest of the wiring and charging system. Defective or faulty fan control relay 3 4. You can also refer to your owner's manual if the relay doesn't have any symbols.Resistance Test: 1. The fan relays are nothing but a remote light switch. This will allow mounting of the fan(s) without compromising the core of the radiator. That saves a lot of time because you don’t have to refer back to the component locator or circuit locations. - The vehicle speed is less than 38 MPH. The cooling fan relay coil receives the Ignition Voltage directly. There are multiple factors that can lead to this error code. 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. your question in our FREE car repair forums. 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. Refer to the top or side of the relay to locate these terminals. 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. 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. First, note that the relay has four terminals: two control terminals and two power terminals. Faulty cooling fan 1 3. Faulty cooling fan 3 5. 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". The fan that is not in front of the air conditioning condenser is the main cooling fan and the one to concentrate on initially. The first part of the installation is to install the electric fan to your radiator, and remove the mechanical fan. Dodge Radiator Fan Wiring Diagram. The schematic will help you also when checking the fan cooling circuit. Open or shorted fan cooling fan harness 3. Check the electrical connection at the fan. Reconnect it and warm the engine. If you’re tracking down a wiring issue, Eautorepair.net is the better choice. It does so by supplying the ground to the relay. Contact Us Most late model vehicles use an electric fan to pull air through the radiator. The bottom of the fuse block lid will usually indicate placement, but if not, look in the owner's manual. Spin the fan with your finger (make sure the vehicle and key is off). 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. The PCM (powertrain control module) senses the increase in engine temperature through the CTS (coolant temperature sensor) located near the thermostat. If you still need help regarding the P0480 trouble code, please post - The vehicle speed is less than 38 MPH. Anyone know where the relay for the cooling fan is? See the schematic printed on the relay itself or consult the schematic in your vehicle repair manual, if necessary. 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. Look at the circuit diagram displayed on the side of the relay. The PCM controls the cooling fan by grounding the cooling fan control circuit which turns ON the cooling fan relay. Get the BEST auto repair information Alldatadiy.com and Eautorepair.net are professional-grade shop manuals—period. Set the … All information on this site is copyright protected. DIAGNOSTIC TROUBLE CODE (DTC) - P0481 HIGH SPEED COOLING FAN RELAY CIRCUIT FAULT (WITHOUT A/C) Details of the Circuit. 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. A/C refrigerant pressure sensor 10. Some Dodge vehicles have a solid state radiator fan controller that varies the fan speeds by pulsing the ground to the radiator fan motor. If necessary, a replacement relay costs around $20.There are three ways to check for a bad terminal. Defective faulty fan control relay 1 2. 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