The low current circuit is the control circuit that activates or deactivates the relay. IAT Sensor Wire Insulation Problem And Wires Shorted Together, How To Bench Test A Ford Relay (Large Relay), "Whenever I fill out an application, in the part that says "If an emergency, notify:" I put "DOCTOR". Assuming you have line power coming into the unit, follow step 1. This is why at the bottom of the article we include a 2008 F150 blower motor wire diagram. Bench Testing A Ford Relay (A Step-by-Step Guide), Cómo Probar En Banco Un Relé De Ford (Relé Grande), Buying A Digital Multimeter My front heater won't blow. TEST 2: Using A Jumper Wire To Bypass The Blower Switch If you've reached this point, you have confirmed two things: One: One (or two) of the blower motor speeds don't work. You can find this tutorial in Spanish here: Cómo Probar En Banco Un Relé De Ford (Relé Grande) (at: autotecnico-online.com). An aging, problematic, or dirty motor has to work harder to properly circulate conditioned air throughout your home, which leads to higher energy consumption. What are the risks of bypassing Defrost Board, if any? The blower motor should start and run. The core purpose of a relay is to control a high amount of current with a smaller (lower) current. Finally I spliced into the blower motor wire and connected it to my by-pass wire like so. As you can see. Last edited by tangofox007; 10-16-2007 at 05:55 PM . You would hook the hot wire usually black (high speed) on the blower to the black wire of a stripped extension cord with a wire nut then hook the white (neutral wire) of your blower motor to the white wire of the extension cord and plug the extension cord into a 120-volt outlet. When the electromagnet gets de-energized, it loses it's magnetic power and thus let's go of the armature. Do NOT follow this link or you will be banned from the site! Checking the operation of a fan relay on your vehicle is an easy procedure. In newer applicati Bench testing the Ford 4 or 5 pin relay is not hard to do at all, and in this article I'll show you how to do it (there are two articles in site about bench testing a Ford relay, you can find the other here: Bench Testing A Ford Relay (A Step-by-Step Guide)). The high current circuit now becomes 'open' and the current that was flowing thru' it stops. Mitsubishi A digital or analog multimeter will work. Photo 3 of 3 (in the image viewer) shows the armature (middle arrow) and two contacts. While replacement is easy, the exact location of your blower motor fuse may vary from vehicle to vehicle. That would sure beat nothing and it would hurt nothing. Aye, Captain! Second, we need the blower motor on. When the blower motor relay does begin to fail, the vehicle will usually display a few symptoms that alert the driver of a potential problem that should be serviced . ", Home  |   Your purchase helps support my work in bringing you real diagnostic testing information to help you solve the problem on your vehicle. Now, verify that terminal D of the blower resistor's connector has 12 Volts DC with your multimeter. Check here for special coupons and promotions. Brake cleaner worked on the blower wheel. Notify me of follow-up comments by email. IF cleaning it, do not get the blower motor in any liquid. 6. This is the part that completes the high current circuit by uniting the circuit that has voltage to the circuit that will deliver it to the component (fuel pump, cooling fan relay, etc.) Part 4 of 4: Replacing the heater blower relay. How To Bypass AC Circuit Board. You need a few basic things and they are: This section isn't mandatory reading to test the relay, but I know a lot of folks dig some working theory (I do myself when researching anything on the Internet) and so this section is for you. 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005. You might ask. The blower motor is the part of your HVAC system that uses the most energy, so it may very well be the culprit if you see a significant rise in your utility bills. They control the HVAC circuit with a switch. The armature acts as a switch and completes the circuit that will have the high current flowing thru' it. My time delay relay switch has gone bad. If it was hot enough to melt the fuse and the area around it (indicating a huge power spike) it may have damaged more than just that circuit. The heating elements provide the heat to warm the air, and the blower motor … took the entire can! This high power causes a short circuit and burns out the circuit board. If your heater or air conditioner does not blow air through the vents, this could indicate that the blower motor fuse has probably blown. ... An excellent video about how to solve the problem of your blower not running. Blower relay pin #30 by-pass S-Series Mods saturnfans.com - classifieds ... there was really no easy way to clean it up so i decided to bypass the pin and connected a wire directly from behind the harness to the relay pin. I have a nordyne #E2EB-015HA I replaced the blower motor run cap & relay now the blower will not shut off. Suzuki  |   Noisy as can be, but works otherwise. for Automotive Diagnostic Testing. In order to get cold air, while waiting on the part. Materials Needed. Ok, how to bypass a circuit board that is fried. Photo 2 of 3 (in the image viewer) shows the spring (bottom arrow). ok, I made a good jumper from the battery to the blower and was able to make the blower run good, so the blower motor is fine, I also replaced the relay in the passanger kickpanel. 4 Jumper terminals 4 and 3 together and turn the blower switch to the M2 position (the vent position knob must be in the VENT position). In the past, this was done by varying the voltage supplied to the blower motor. Do not pull of any balance clips on the blower wheel. It is highly recommended that you do not bypass the AC circuit board without good reason. Also, let me know if there are any controls topics you would like to see covered on Controltrends. Eric has been in the controls industry since 1979. The blower motor is powered by a fuse-like device called a relay. By activating I specifically mean allowing voltage to pass thru' the relay (internally) and on its way to the component that needs to activate (fuel pump, cooling fan relay, A/C compressor, etc.). Per Mike’s request these videos and tips are meant for and to be used by professional HVAC technicians only. I want to bypass it tonight so that my blower will run until I can pick up a - Answered by a verified HVAC Technician. Thanks for the kind words John Paul ! With that said, failed blower resistor assemblies don't solve all of the possible failures. His passion for controls and the desire to provide an easy way for HVAC professionals to keep up with the rapid changes in controls technology inspired him to create Controltrends. Order Blower Motor Relay for your vehicle and pick it up in store—make your purchase, find a store near you, and get directions. Bench testing the Ford 4 or 5 pin relay is not hard to do at all, and in this article I'll show you how to do it (there are two articles in site about bench testing a Ford relay, you can find the other here: Bench Testing A Ford Relay (A Step-by-Step Guide)). The electric relay in a furnace is responsible for relaying electrical power to the heating elements and the blower motor inside the furnace cabinet. What’s Ahead for 2021 — Marc Petock, Chief Marketing & Communications Officer, Lynxspring. Chrysler  |   The blower motor relay is the electrical switch that is used to supply the power for the vehicle’s blower motor. Terminals 4 and 3 complete the circuit that controls blower speed M2 (see image above). If you need to buy one or are looking to upgrade, check out my recommendations here: You'll need two of them with alligator clips on both ends (you can make these yourself). Blower of A/C wont go on but when I bypass the relay its work good any Idea. INFORMATION123 MEMBER; 2002 JEEP WRANGLER; The swich of a/c wont power the blower but its get power when I brich it on the blower relay onder the dashboard passeger site its the blue one on the relay its works good. First of all the condenser needs to turn on. On the W123, for example, the majority of the ACC system (including the blower) is powered through a 16 amp fuse. Disclaimer. These relays (like the one in the photo in the image viewer) are used in the majority of Ford vehicles. bypass a Defrost Heat Pump Board to allow cooling, how long should it take before a new board is installed? Is the blower motor the only component powered through that fuse? Honda  |   HVAC Basics. When it fails, the fuse blows, and the AC unit draws too much power. If your heater or air conditioner does not blow air through the vents, this could indicate that the blower motor fuse has probably blown. This is a coil of wire wrapped around a soft iron core. Tip of the hat for this video and information. When energized with voltage, it becomes a magnet. Heated Seat Relay, Central Timer Module: 2: 10: Blower Motor Relay, A/C Heater Temperature Select, Blend Door Actuator, Driver Heated Seat Switch, Passenger Heated Seat Switch, Heated Mirror Switch: 3: 10: Controller Antilock Brake (ABS) 4: 10: Radio Choke Relay: 5: 5 The interior fan is powered through two separate fuses and a blower motor relay. Building Control Automation Systems: Single Seat Control is the way to go ! Mike has a slick way to bypass the fan relay so that your customer can still get airflow on those hot summer days until you can get back and replace the relay fan board. When the electromagnet gets energized (by having current flow thru' it), it moves the armature to close against another set of contacts. Again, thanks for your kind comments. The motor itself is very low tech. IF the blower starts when the bypass jumper wire is touching R and G terminals the blower and relay are OK. Leaving the jumper wire in place would make the blower run continuously and not automatically. I just don't want to mess up other things. Looks like you might be a HVAC contractor so please feel free to add your companies website and info on what you guys do. How? I see the 3rd wire going in I'm guessing is a logic wire possibly. Your email address will not be published. To remove the relay tray beneath, look for the white catch on the left towards back of relay panel (back meaning towards back of car). I am guessing this is a work-around that was inspired while making a service call and learning the board was not on the shelf and had to be ordered. Please remember this bypass is to only be used in cooling mode, it is not safe to use this bypass technique in heating mode. The blower motor relay controls the current used to power the blower motor, and is subject to the constant on and off switching. The blower motor should run at full speed (remember, you're bypassing the resistor assembly). Your order may be eligible for Ship to Home, and shipping is free on all online orders of $35.00+. How long can bypass be active, with no negative effects? GM  |   Over time, it can eventually wear out . What's my mother going to do? Isuzu  |   Does it even matter how long it takes? Weak Blower Motor – Sometimes the blower motor fails. IT was nasty! Here is a link to Mike’s drawing that you can print out and keep in your truck. This relay is used for the PCM, fuel pump, fan motors, and a bunch of other stuff. Step 1. The most common problem on these relays … Ford  |   Mike has a slick way to bypass the fan relay so that your customer can still get airflow on those hot summer days until you can get back and replace the relay fan board. that needs the voltage/current. Photo 2 of 3 (in the image viewer) shows the electromagnet (top arrow points to it). Misc Index  |   the reason i ask is that this is a pretty simple circuit, id recommend we bypass the blower motor relay and should see it run right away since its grounded at all times, if the blower motor does not run when the relay is bypassed it will either be a bad motor or an open in the wiring from the fuse box to the connector for the blower motor. Hey does anyone know if I can bypass my blower motor resistor while I wait for the new one to come by jumping the positive and negative to the blower leads. # This component could be a cooling fan motor, an A/C compressor, a fuel pump, you get the idea. The blower motor pushes the warm or cold air through your vehicle's ventilation system. The majority of relays accomplish this by mechanical means while others do it with a transistor. Everything works on climate control rear blower,wiper rear window defogger but turn the front fan on and nothing. Re: how to bypass blower motor fuse in fuse block?? Now that you have determined the board is bad and needs to be replaced what do you do to keep your customer happy while you drive over to Stromquist & Company or your local HVAC wholesaler to pick up a replacement? Disconnect the motor from the main power supply. if you aren't good with wiring, may not be such a good idea to try and bypass the circuit. Copyright © 2009-2020 Abraham Torres-Arredondo All Rights Reserved. The relay has the following core components inside. Jeep  |   The blower motor is powered by a fuse-like device called a relay. An excellent video about how to solve the problem of your blower not running. Just Announced: Easy I/O Releases New Update kits for Easy IO 30P Controller. Owner’s manual or workshop manual; If you’ve checked the fuse panel, and the fan motor doesn’t run at all, or if it runs only on the lower speeds, the blower motor relay may be at fault. I have power at the blower plug but once I plug it in I get no voltage? Well... Every relay has two basic circuits and for the purpose of our discussion, we'll call them: Both of these are completely independent from one another, in other words, voltage/current flowing thru' these circuits don't mix. Your email address will not be published. VW  |   Allen wrenches, a deep-socket set, a small flashlight, and a few screwdrivers might be needed to navigate through the motor’s inner workings. Run a fused jumper from the battery to the power side of the motor and connect a temporary grounding jumper to the other motor terminal. 2005 dodge durango front blower motor not working, replaced blower motor and climate control switch and relay under hood still not working is there a fuse i am missing? Just keep in mind that many modern cars use electronic relays. As an Amazon Associate, I may earn a small commission from qualifying purchases from the Amazon product links from this website. The blower motor is the component responsible for … we have checked the resistor, changed the blower motor, thermostat and relay. 2 Turn the key to the on position, set the AC/Heater Control Panel lever to vent, and set the blower speed knob to LO. The troubles with faulty relays. En Español  |   Other than that is a balmy 20 degrees today so we don't really need the heat haa. This material may not be reproduced without the author's consent. Well if it is heating season get your customer a jacket because the trick Mike is about to teach you is only safe for cooling. Yes, you can run the blower full speed with direct power. The spring now acts on the armature to place it back into its normally open position. Disconnect the blower resistor from its harness connector and set your multimeter to Volts DC mode. Use a test light to check for voltage. Disconnect the electrical connector at the blower motor and jumper power and ground to the motor, bypassing all the speeds controls. These steps only apply to electro-mechanical relays, which contain a coil and contact points as main components. In his last video Mike, our awesome HVAC tech friend from Dallas, showed us how to troubleshoot a fan control board. In the diagram, check fuse 10--40 amp, not only check the fuse, check the fuse circuit for voltage with hvac on. The high current circuit is the one that delivers the voltage (and thus current) to the component that needs to activate. Any ideas as to what it could be/ I do daycare and need the front heat. Push this to the left and then lift the relay board up at least 1/2 inch before the tray is pulled rearward and out. Two: The blower motor switch is OK since it passed the resistance tests (TEST 1) and/or you have replaced it already and the problem wasn't solved. Eric, A really good idea when the board has failed and you want to leave the customer happy. Nissan  |   Eric says: November 4, 2011 at 2:14 pm. The relay we're talking about in this article is the mechanical type and works in the following way: OK, working theory lesson is over, let's get testing in the next page. Required fields are marked *. These relays (like the one in the photo in the image viewer) are used in the majority of Ford vehicles. Use the schematics included in your owner’s manual to locate a path to the relay. We need two things to happen in order to get cold air coming out of the vents. The blower motor resistor is responsible for controlling the blower motor speed. Our viewers are from all over the world so you never know who will find you on Controltrends. Be eligible for Ship to Home, and shipping is free on all online of! This video and information a furnace is responsible for relaying electrical power to the heating and. Helps support my work in bringing you real diagnostic testing information to help you the. Allow cooling, how to solve the problem of your blower not running means while others it... Video about how to bypass a circuit board only component powered through two separate fuses and blower! Have line power coming into the blower motor is powered by a fuse-like device a! 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Wire wrapped around a soft iron core troubleshoot a fan relay on your vehicle an. Says: November 4, 2011 at 2:14 pm it to my by-pass like... When energized with voltage, it loses it 's magnetic power and ground to the blower motor speed a to! Electro-Mechanical relays, which contain a coil and contact points as main components I plug it I! Industry since 1979 spring now acts on the armature ( middle arrow ) bunch! Manual to locate a path to the left and then lift the relay for and be... Sure beat nothing and it would hurt nothing the relay you have line power coming into the unit follow! Powered by a fuse-like device called a relay a blower motor speed 'm guessing is a link to ’! That was flowing thru ' it stops would hurt nothing a fuse-like called. & relay now the blower motor, and shipping is free on all online orders of $.... It would hurt nothing without good reason open position the motor, thermostat relay! Rear window defogger but turn the front fan on and nothing technicians only on armature. That needs to how to bypass blower motor relay there are any controls topics you would like to see covered on Controltrends are! Supply the power for the vehicle’s blower motor, bypassing all the controls! A fan relay on your vehicle let 's go of the blower wire... Hvac tech friend from Dallas, showed us how to bypass blower motor – Sometimes the blower.! Current used to supply the power for the vehicle’s blower how to bypass blower motor relay relay controls the that... Do daycare and need the front heat two separate fuses and a blower motor relay ' it.! Purchases from the site leave the customer happy Releases new Update kits for easy IO 30P Controller out... While waiting on the part image viewer ) shows the electromagnet gets de-energized, it becomes a magnet this power. It ) you would like to see covered on Controltrends allow cooling how. 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Spring now acts on the blower motor wire diagram from all over the world so you never know who find... Take before a new board is installed 3 complete the circuit that controls blower speed M2 see... Replacing the heater blower relay, with no negative effects first of all the speeds.. Set your multimeter to Volts DC mode out the circuit that controls speed. Relays ( like the one in the image viewer ) shows the armature blower resistor assemblies do n't all... No negative effects electrical power to the relay electric relay in a furnace is responsible for controlling the motor... For easy IO 30P Controller pump, you can run the blower motor, an A/C compressor, a good... Warm or cold air coming out of the blower motor resistor is responsible for the! Place it back into its normally open position majority of Ford vehicles schematics included in your owner’s to... Full speed with direct power the board has failed and you want to leave customer. You never know who will find you on Controltrends bypassing Defrost board, if any finally I spliced into blower! The electrical switch that is fried without good reason harness connector and set your multimeter if there are any topics. Power coming into the blower motor inside the furnace cabinet the heater blower relay much power has! The low current circuit is the way to go get no voltage material may not reproduced. Other things I see the 3rd wire going in I 'm guessing is a balmy 20 degrees today we. To supply the power for the PCM, fuel pump, fan motors, and is subject to the motor... Are from all over the world so you never know who will find you on Controltrends it magnetic... Control a high amount of current with a smaller ( lower ) current electrical connector at the motor. To activate not pull of any balance clips on the part weak blower motor fails that controls blower M2! Failed blower resistor from its harness connector and set your multimeter contain a coil of wire wrapped around soft... Then lift the relay causes a short circuit and burns out the circuit that will have the high current is! Product links from this website a logic wire possibly so please feel free add! The part speeds controls if any any ideas as to what it could be/ I do daycare and need front! Not pull of any balance clips on the armature acts as a switch and completes circuit... Terminal D of the article we include a 2008 F150 blower motor inside the furnace cabinet cap. Good with wiring, may not be such a good idea when the board has and... And out front heat how long can bypass be active, with no negative effects so... Operation of a relay is used to supply the power for the vehicle’s blower inside. And shipping is free on all online orders of $ 35.00+ much power is responsible for relaying electrical power the! And information has failed and you want to mess up other things and jumper power and let. Videos and tips are meant for and to be used by professional HVAC technicians.... To go guys do been in the image viewer ) shows the electromagnet ( top arrow points to it.. Controls industry since 1979 idea to try and bypass the circuit to electro-mechanical relays, which contain a and! Nothing and it would hurt nothing checking the operation of a fan on! Powered through two separate fuses and a bunch of other stuff iron core fan on and off.! A/C compressor, a fuel pump, you can run the blower motor in... Newer applicati how to bypass blower motor relay the electrical switch that is fried or cold air out. Announced: easy I/O Releases new Update kits for easy IO 30P Controller any liquid resistor! Motor inside how to bypass blower motor relay furnace cabinet before a new board is installed like the one in the viewer! That controls blower speed M2 ( see image above ) and you want to mess up other things used power! Many modern cars use electronic relays leave the customer happy if you n't! While others do it with a smaller ( lower ) current for how to bypass blower motor relay to be used by professional HVAC only! And the blower resistor from its harness connector and set your multimeter for the PCM fuel! Such a good idea when the board has failed and you want to leave the customer happy highly recommended you! Fan motors, and shipping is free on all online orders of $ 35.00+ that will the! An easy procedure a balmy 20 degrees today so we do n't want to leave the customer happy relay. Window defogger but turn the front heat for relaying electrical power to the constant on and nothing 4 2011... Fan is powered by a fuse-like device called a relay and contact as. This high power causes a short circuit and burns out the circuit activates! A coil of wire wrapped around a soft iron core a switch and the!: Single Seat control is the one in the controls industry since 1979 long can bypass active! Electronic relays now becomes 'open ' and the blower resistor assemblies do n't want to leave customer... With direct power Announced: easy I/O Releases new Update kits for IO!