I realized that the radiator and condenser cooling fans were not coming on when needed (after a half hour of the engine running) so I pulled the relay switch and used a paper clip to "jump" it and the fans came on. 3,084 satisfied customers. is the motor fan's broken? 29,095 satisfied customers. OK the radiator fan switch will ground the relay in the J/B 2 on the left side of the engine comp, which also goes through the A/C high pressure switch causing the relay to hold contact open. the radiator popped because it was old and after a couple weeks of the fan not doing its job i guess it just got too hot and cracked. Service Center Owner / Technician. My radiator fan is driving my crazy. Anything else is likely to have an adverse effect – and that often manifests as banging, clanking or gurgling noises. Refill the radiator, test it, and add some corrosion inhibitor to stop rust. Did you check to make sure power is going from the hot wire to the fuse block for the fans? Joined Apr 20, 2008. sorry to bring back a thread from the dead but im having the same exact issue. Favorite Answer . High School or GED. But never are they both on at the same time. Fan Selection: Depending on vehicle design, the fans may operate singly or in tandem. 8 years ago. Answer Save. Whenever I drive it on the highway for one hour or more, the temperature meter gets to half guage. My car is an 05 5.7, here is my problem. The sensor may be disconnected, lose, or corroded, or wire broke. If the radiator fan is in working condition, move on to the next step. Thermostat. It is what sends the signal for the fan. Lv 7. Jun 18 2018, 5:54pm. How does a car’s cooling fan work? One fan will come on when the vehicle temp hits between 180+ to 210+. It looks like I've got two main fan relays and a sub fan relay that I'll have to check. If so switch the plug to the other fan and it should come on. It is a 2001 . The Cause: If just one of your radiators is not playing ball, it could be down to either a faulty or jammed valve, or alternatively a blocked pipe could be the culprit. It is supposed to kick in around 105C or 106C I unplugged the radiator power connector and put a multimeter across the plug terminals and read no voltage even when the temp was at its highest. Nothing physical blocking it. it worked so its not the fan motor. Same fan comes on when the A/C is turned on. YES - Go to step 5. The fact that it is compatible with RGB Fusion does NOT make it work! Ask Question Asked 4 years, 3 months ago. Thus, my car will overheat in city traffic (but not on highway). The fans needed to be replaced and fell apart as soon as I removed them from the engine. The cooling fan one relay controls the passenger side hi speed cooling fan, whichis working correctly as you state. Run jumper wires between the connector's two electrical terminals. Only one of the dual fans works. Even when I turn on the AC, only one fan works. To start with, there should only ever be two things inside them: water, and central heating inhibitor. There should always be at least one fan on when A/C is on, except at highway speeds all fans may be disabled. If I unhook the temperature sending unit both fans run continuously. Radiator fan testing points. Subaru and Nissan factory training. Fans work, both heater and radiator. Does the one fan come on with the a/c? Discussion Starter • #1 • May 15, 2010 (Edited) Hi everyone. the other side will not turn on. If anyone has any advice or … my radiator fan works perfectly but ONLY if i have the AC turned on. Larger parts stores may have them on the shelf. When is this fan supposed to come on: at what temperature and when? Seized Motor. Both fans come on when the A/C is turned on. Water pump seems to be working. See Contact Test in Step 1. 57 Posts . 2005 Honda Accord: 2.4L..cyl..a coolant bleed screw..radiator. Your cooling fan comes on when the car reaches a particular temperature. If the fan does not turn on, you will need to replace it. AG 305 Proven Member. The temp increased to to 109C and the radiator fan didn't kick in. On some vehicles, for example, only the condenser fan operates with the air conditioner, while only the radiator fan operates based on engine temperature. Your car’s cooling fan, or radiator fan, plays an important job in keeping your engine cool. 555 1. I checked the connection and that was fine, the fuses were also fine. Both fuses are good. Only one radiator fan running. Your Mazda Miata‘s radiator fan has one of the most important jobs on the vehicle. Multiple relays and resistor packs may be used to control fan activation. Yes, a broken radiator fan can cause the air conditiong to stop working. Any suggestions? If only one of your car's two fans works, then the problem is either a burned-out fan motor or a bad electrical connection between the affected fan and the wiring harness. That software can control BOTH types of hardware RGB systems, depending on which type of header is included on the Gigabyte mobo. It is the last line of defense between you and an overheating engine. You really need to have the fan replaced, or at least, have a diagnostic check to see what is causing the fan to stop working. Electric cooling fans for radiator run when AC is turned on. Viewed 5k times 3. Figure 3. Tested the fan with 12V when the fan was out of the car. Does anyone know if losing one of these relays would knock out both fans? If it stops working, your engine could overheat and be damaged. Show more. Then you know it is your fan switch. How Radiator Cooling Fans Work. Today while adding coolant to my car, I noticed that once the car reached running temperature only the fan on the passenger side had turned on. One post advised that if the power steering fan seized (which was quite common), the fuse would blow, rendering the radiator fan useless too. The cooling fan in a Jeep Grand Cherokee keeps engine temperatures at the correct level by kicking on during times when the engine reaches higher-than-average temperatures. Your fans work through a thermocouple relay. One fan comes on at 227 degrees and goes off at 217 degrees. Now, it turns out that your case has the plain RGB type of RGB fans, based on the case website. I have replaced the temperature sending unit. I changed the whole fan assembly and both relays, but still only one fan will come on. Miami, Florida. A bad sensor will tell the car that everything is normal while the engine overheats. So i got a new radiator and installed that. I tested it and it gets power when I just do it myself but it will turn on … read more. Does the radiator fan run? The AC system depends upon being able to dissipate heat into the engine coolant. The trigger is the thermostat in the radiator of your vehicle. @ Tallra1 I already checked the wirings, and its all in good shape, but i havent check yet the main thermo-switch. Electric radiator-fan motors are switched on either by the ignition switch - and run while the engine is working - or by a thermostatic switch. What else can I check? Sometimes they alternate. There are a number of common problems with radiator fans, and if your vehicle has one of them, fixing it is relatively quick and cheap to administer. silentbravo wrote:Those square fuses are called J Case fuses, sold by Littelfuse. Okay so i replaced my radiator and now my fans dont turn on. Just because the radiator fan is not on does not mean that it is not working. The thermocouple relay may be bad, of the temp sensor is bad. the radiator fan only one side kicks on. The only other thing I can think of is a wiring or computer problem. I've checked the fuse in the footwell and it is fine. My 1st stage was obviously out of action due to the resistor, but at some stage the PS fan had seized, blowing the fuse and disabling the 2nd stage fan. Thermostatically controlled motors do not work the fan until the engine coolant rises above normal operating temperature, and then switch off when it has cooled down again. The radiator fan does a very important job; it cools the radiator to stop the car from overheating. @johnblack I checked it while it is on cold state, but then when turn the AC ON the Radiator Fan turn on, so I let the AC ON while i drive my car, after 30mins driving if i turn the AC OFF, the RADIATOR FAN still dont work, even the Radiator Temp was hot. Changed the cooling fan relay thebesthonda. Re: Electric cooling fans not working . The fact that the driver side hi speed fan does not come on when commanded to points to the relay that is called "fan contro relayl".This relay is pcm ground side controlled, together with the "cooling fan 1relay". Why does my fan come on when I start my car? I have a 1995 subaru legacy. Unplug the radiator fan connector. Aug 12, 2011 #13. Relevance. the ac will not work. If you have problems with the radiator fan, you need to take care of them immediately or you could cause serious damage to your car. This article pertains to all vehicles. You can rest assured the fans work. Long story short, I've since replaced the thermostat and the radiator fan switch (located in the thermostat housing). Surprise. The temp light comes on and if the fan kicks on, everything is fine. Works great for a while then only sometimes. They are designed to only run when needed. As soon as I approach a traffic stop light, trying to press … read more. Step by step instruction on how an automotive radiator cooling fan works. If the radiator valve does not turn in that direction, try turning it in the other direction (clockwise or "closed") to see if the radiator valve is stuck. I have replaced thermostat. Here’s how to tell if your cooling fan isn’t working, what you should do about it and what the problem might be. Sometimes the fan does not kick on at all. When the switch is unplugged the ground will go away and the relay will close, (normally closed relay), (normally closed switch). Why does the radiator fan on my Kawasaki Mule 3010 only work inadvertantly? Candid Chris. When I disconnect the temperature sending unit the temperature gauge in the car does not work. Does that mean power isn't getting to the fan? I have checked the relay and it is good. Step 1 - There are primarily two types of engine radiator cooling fan, electric and manual. Symptom 3: A single radiator is cold/not working . You may also find the same control valve at heating convectors (but not usually at heating baseboards). The inhibitor is a chemical which stops corrosion by preventing the water from reacting with the metal of your radiators. Other fan does not come on and it is a new fan. If your fans do not engage and the dashboard temp gauge reads normal, then the thermostat sensor is bad. I got under the car again and found that the PS fan is indeed totally seized. 960 Posts . Without it, the engine can reach dangerous temperatures and damage engine components. Mike V. Subaru Technician. Active 4 years, 3 months ago. If the radiator fan is not working, it’s a serious problem. Discussion Starter • #1 • Mar 6, 2011. I have a 1992 C4 Corvette. If the cooling fan stops working, most do-it … 2 Answers. I did replace the fans with similar ones from an Impala in the junkyard, plugged both fans in and bolted them onto the radiator, so everything appears to be hooked up right. 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