One of the first symptoms commonly associated with a bad or failing cooling fan relay is; an engine that runs hot or overheats. The relay is the component that fails most often; so be sure to test the relay as well as its power supply and ground connections. If resistance is high, the coil may still be working but it is failing; or it may not work when electrical loads are high. The relay(s) are used to control the high current flow to power the cooling fan motors. CASE 2: Fan motor 2 DID NOT come On. Think mine has gone just want to test it to make sure, its a 2001, 2.5 v6 Also has the main engine fans meant to come on when the a/c is on? The Next Thing To Test Is The Coolant Switch Or Sensor On most systems; there is a coolant temperature switch that turns the fans on and off. We do not intend to infringe any legitimate intellectual right, artistic rights or copyright. As you touch ground with the jumper wire, you should hear a click sound coming from the relay. How to Reset the Immobilizer on a Jeep ... Photo courtesy of Leonard G. at Commons Wikimedia.org. If one or both fans fail to come on; the lack of additional cooling provided by the fan may cause poor A/C cooling performance. Watch this video to figure out how to diagnose problems with the cooling fan relay on a Chrysler. Also, it may cause the A/C compressor to overheat and fail. COPYRIGHT © 2021 DANNYSENGINEPORTAL.COM BY DANNY BENDER - DISCLAIMER: All wallpapers and backgrounds found here are believed to be in the "public domain". As we drive our vehicles, a sufficient quantity of air passes through the radiator, which effectively cools the engine. While you are driving, air in sufficient quantity is passing through the radiator effectively cooling the engine. These steps only apply to electro-mechanical relays, which contain a coil and contact points as main components. This test result let's you know that fan motor 2 is OK. As the name suggests, many sensors are incredibly sensitive pieces of electronic equipment and produce only small electric currents. You should read infinite resistance. The engine may also run hot and overheat, too. 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. Possible Causes of a Bad Cooling Fan Relay If you read any amount of resistance, the relay contacts are stuck closed and the relay should be replaced. The … The fan relay controls the power to the cooling fan. When the vehicle is not running, then there will be no air passing through the radiator. Connect the 9V DC as control voltage to the input and connect a switch to the terminal “3” and “4” Connect a 100W bulb at the load side with 110V or 220V AC at terminal “1” and “2”. Copyright 2020 Leaf Group Ltd. / Leaf Group Media. You should read infinite resistance. Now you should read zero resistance. Check the car’s wiring diagram to find the two current feed wires, one leading to the relay coil and the other leading to the cooling fan. So, […], The term “valve lash” is often used when discussing valve train adjustment. But often we need them to drive bigger pieces of apparatus that use bigger currents. Leave the jumper wires connected to the relay control terminals if you heard the click sound in the previous step. The relay will usually be activated once it is detected that the vehicle’s temperature approaches excessively high temperatures. If you are the rightful owner of any of the pictures/wallpapers posted here, and you do not want it to be displayed or if you require a suitable credit, then please contact us and we will immediately do whatever is needed either for the image to be removed or provide credit where it is due. Since 2003 Dan Ferrell has contributed general and consumer-oriented news to television and the Web. Faulty wiring could be to blame. Attach the end of a regular jumper wire to the other terminal of the control circuit on the relay and touch the other end to ground on your vehicle. This is a generic powertrain diagnostic trouble code (DTC), which means it covers all makes/models, 1996-newer. Timing Belts – Why Should You Replace Your Engine Timing Belt, Engine Spark Knock – That Annoying Knocking, Pinging Or Rattling Sound, Tailpipe Smoke – What Does The Color Of The Tailpipe Smoke Mean, Engine Coolant Leaks – How To Find Them – How Bad Are They, Valve Lifters – Hydraulic And Mechanical – What Is The Difference, Radiator Cap – Basic Function – Failure Symptoms – How Important Is It, Engine Bearing Replacement – Learn How To Replace Engine Bearings, PCV Valve System (PCV) (Positive Crankcase Ventilation System), Radiator – Overheating, Causes, Consequences And Maintenance, Spark Plug Problems – Troubleshooting, Failure Symptoms, Replacement, Vacuum Leak Repair Locations – Common Causes – Common Repairs, Valve Lash – Getting All The Facts For Setting And Adjustment. Thanks lads n gals. The quickest way to tell whether or not the electric fan(s) are working is to start the engine; let it reach normal operating temperature and then turn the A/C on. To test a solid state relay, follow figure and steps given below. This means the relay contacts are operating normally. How to Test a Relay. His work has appeared in Texas, New Mexico and Miami and on various websites. The armature is normally closed and is pulled open when energized. Heat/ Defrost fan fuse number 7 inside drivers dash fuse box. The cooling fan relay is the relay that controls the engine’s cooling fans. Example: Testing the radiator cooling fan relay, the cooling fan should be operating. Oil Leak In Spark Plug Well – Know The Signs – What Can Happen, Broken Bolt – Stud Removing – Repair Tips To Save You Time And Money, We all know it’s important to take care of your vehicle’s engine; but some common engine problems can get overlooked. Replace the relay. In most cases, the two thin wires connect to the control circuit and the two thick wires connect the power terminals on the relay. A relay uses a relatively small electric current that can turn on or off a much larger electric current. See the Tips section at the bottom for more information. Using your ohmmeter as described on step 2, check for continuity at the relay's power terminals. If your fan relay does not have markings on it, you will have to consult the cooling fan wiring diagram found in your vehicle service manual. Connect your test light to battery ground. Check out some of my other posts if you need more tips and info." Relays are discrete devices (as opposed to integrated circuits) that are used to allow a low power logic signal to control a much higher power circuit. Checking the operation of a fan relay on your vehicle is an easy procedure. A wiring issue. - The … Be sure you have the right one. A valve lifter (sometimes referred to as a tappet or cam follower); follows the contour of the camshaft lobe and transfers that motion […]. Switch it on with a tiny current and it switches on (“leverages”) another item using a much bigger current. As I say, having removed the shroud, I am at the stage where I want to test the relays in … Engine cooling fan, 50 amp fuse,at the power distribution center or relay box at engine compartment. - The A/C clutch requested. 1. With the relay in the configuration that has the 2 load pins connected, place the test voltage on 1 of the load pins of the relay and an automotive test light on the other load pin of the relay. Pip When the correct parameters are met, a temperature switch or the computer will activate the relay, which will allow power to the fans. The quickest way to tell whether or not the electric fan(s) are working is to start the engine; let it reach normal operating temperature and then turn the A/C on. You will find the resistance of the relay coil. Non-functional cooling fans are another common symptom of a potential problem with the cooling fan relay. Although the water pump in most vehicles will last a long time, they are by no means indestructible. A faulty cooling fan relay can also negatively affect air conditioning (A/C) performance. You should be able to conduct an Output Test with the ECM (key-on, engine-off). So, as a vehicle owner it is important that you’re; constantly on the lookout for […], To start with, Water Pump Failure can be extremely hard to diagnose. Relays bridge the gap, making it possible for small currents to activate larger ones. Finally, if you suspect that your cooling fan relay, may possibly be having issues, have it checked. Engine Antifreeze Coolant – What Does It Do ? If there’s an issue with the relay, the fan will be affected. You do not need the Jeep factory scan tool, just a generic scan tool that you can buy at your local auto parts store or online and a multimeter. The cooling fan in the engine compartment should turn on to pull air through the radiator and A/C condenser. 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