Your DVOM should read battery volts (green arrow). The resistance (ohms) of the windings should be tested. On 2016-05-31 by Anonymous. This is a very easy test and it will let us know if the blower motor uses too much current. This includes powering up the inducer motor, testing operation at low speed for 20 seconds, testing operation at high speed for 20 seconds then powering down. The white wire is called the run wire. Where To Buy The Blower Motor And Save. A 1/4-inch socket will be needed to remove the screws holding the cover. Select ohms resistance on the multi-meter and set for the 30,000-ohm range. Depending on the exact location of the blower motor (on your specific 3.8 liter equipped GM vehicle) you can test it on the car or you may have to remove it for ease of access. This article series discusses how to inspect and test a heating or air conditioning indoor air handler blower fan that is not working. The next subheading will show you where you can buy the blower motor and save a few bucks. To inspect the capacitor, make sure it is discharged. Check for a bad start capacitor or seizes blower fan or motor. Now put your furnace’s blower fan to the test. (The black wire is usually the negative.) Once it is discharged, use a capacitor tester to check the microfarad reading. I have a 2006 Bard Geothermal . Many blower resistors control current to the blower motor in all speeds except high. Another possibility is that the driven load is jammed, binding or mismatched. Delivering torque to the fan motor, if the capacitor is faulty, there won’t be enough power delivered and the blower wheel, fan belt, and other important components can cease to operate. Test the fuse, with the ignition key on, using the 12-volt test light. Testing the blower motor of your home HVAC system If debris is not the problem, use your multimeter to check for voltage in the contacts motor. An A/C blower motor resistor uses resistance to control the speed of the blower motor. Remove the passenger side, lower dash cover under the glove compartment that conceals the blower motor. The white wire is called the run wire. 2. If you see or hear the fan turn on, your blower motor is not the culprit. Æ´XÓ±]Ÿ­é@§u;vŽÍð\(}­Ð%¦VHÛ?ëÎ!¢Ë}ù˜vƒÞ}P±¿'õ!ˆŽÁpK\R+=ª¿Z;¶»¹»+ò&(Ƨɽx»e §d‰Ë. 2. To find out the amperage draw, we'll test the blower motor's resistance. If the motor is direct-drive these numbers can be difficult to read. If power is supplied to blower motor through the speed switch and blower motor resistor: Disconnect the electrical connector at the blower motor. I think i have a bad barring. For circuit descriptions and diagrams, refer to Air Conditioning/Heater in Group 8W - Wiring Diagrams. Perhaps your blower motor has burnt out and you need a new one. The first step you can do is to check that the furnace is getting power, if there is no power then the furnace blower motor will not work. Disconnect the negative and positive power supply. You consent to our cookies if you continue to use our website. It reviews best practices for diagnosing common electrical problems. If the motor does not run, unplug the 16 pin wiring harness from the motor (fig. We also share information about your use of our site with our social media, advertising and analytics partners who may combine it with other information that you’ve provided to them or that they’ve collected from your use of their services. also has a rattling sound when running. Information about the device's operating system, Information about other identifiers assigned to the device, The IP address from which the device accesses a client's website or mobile application, Information about the user's activity on that device, including web pages and mobile apps visited or used, Information about the geographic location of the device when it accesses a website or mobile application. A repair manual can tell you where its location is in your vehicle’s make and model. If the blower motor is not working and no air is being blown through the unit it will overheat and the high limit switch will turn the gas off. Connect the other end to your Ford's battery negative terminal. If the motor itself has developed a fault, the fault may be a burnt wire or connection, a winding failure including insulatio… Both the front blower motor resistor and the optional rear heater-A/C unit blower motor resistor can be diagnosed using the procedure that follows. If you're concerned that your furnace capacitor isn't operating properly, you can test it by following a few simple steps. If the motor is direct-drive these numbers can be difficult to read. Allow the microprocessor to complete the diagnostic procedure for the inducer motor. If there is any reading on any of these then the motor is bad, do not use it. Disconnect power from the blower motor by shutting it off at the disconnect box to the unit or unplugging the power source. Detach the blower motor from its connector. Continued… ECM Blower Motor Quick Test Start car and see if blower motor works. Basic instructions on how to troubleshoot the heater blower motor of a Saturn S-series. Disconnect power from the blower motor by shutting it off at the disconnect box to the unit or unplugging the power source. Locate the blower motor. Blower motor problems can cause many driver complaints. €Ž¹ÝplˆsáÃlê1|¦×¢²FÏØ4Û'9k;YålíJn†«‹7Bá]KÚÓOl3iú®K"Ùc剦>ö½Ã…Úc"‡(”t§=wU¸Š6Ôq ûb€×>½œçº¬k®Ý\£)¹‹\ÞÝaÛ2W ´¹GKâGš¾+~£ÍIû$þÊÂ}ð5Û¼m:º\ˆÆgšM+£ûÖ^b„Ñ)§à˜v}ÿD~Û¢¯¨ÍÃÚâ24çÆïší`}î-EJ“ëR¨,zEj+oHÕ=ÚHz/הŒ,ÚÓùJWÓ! Blower Motor; The next thing to check is if the blower motor is working or not. Then we'll divide the resistance value by 12.5 to calculate it's amperage draw (Ohms Law: Amps = Volts ÷ Ohms). If the circuits are in good repair but the blower motor keeps blowing fuses, replace the blower motor [source: Detach the blower motor from its connector. Once it is discharged, use a capacitor tester to check the microfarad reading. Anything from no air circulation to annoying or noisy operation. Many blower resistors control current to the blower motor in all speeds except high. Step 1 Locate the fuse for the blower motor in the owners/service manual. If a part isn't working properly, clean and oil it, and test it again [sources: Gas vs. Electric Stoves: Which is really more efficient? Unscrew all the screws on the blower motor. At the bottom of this page is a video that’s very popular. I have replaced the resistor pack and the blower motor switch and neither has resulted in a change. Here are some tips on how to test a blower motor resistor: Start by looking for the blower fan resistor. Inspect the capacitor visually for signs of damage. I have a multimeter. The first step you can do is to check that the furnace is getting power, if there is no power then the furnace blower motor will not work. 6). The first step in diagnosing blower motor failure is to check to see if there is demand for the blower. Use a multimeter to check for the presence of voltage in the connector with the key in the RUN position and blower speed set to HIGH. With a multimeter set to low ohms (usually 200), test between each winding terminal and the metal casing of the motor. If you have a reading and your motor isn’t operating, it’s certain the motor is the problem and needs replacing. Take your multimeter and set it to ohms. This test result tells you that the blower motor is bad and needs to be replaced. The Test Procedure 1. An A/C blower motor resistor uses resistance to control the speed of the blower motor. Disconnect it from the motor shaft and set aside. Check for shorts between the power wiring and ground. Put 24 volts to pins 12 and 15 and 24 volt common to pins 1 and 3 at the motor (fig. Touch one lead to each motor power lead and the other to the metal motor casing. Take your multimeter and set it to ohms. It has a shudder on start up. Start by turning the furnace off, turn your thermostat to “fan only,” and wait a few minutes. The amperage draw, of your Dakota or Durango's blower motor should be under 40 amps. Place them in small container. It has a GE 2.3. In this tutorial I'll explain the two tests that you need to perform to find out if the blower motor is bad or not. Using a capacitor tester to test the capacitor. Find the Full Load Amp (FLA) rating of the blower motor. Check for shorts between the power wiring and ground. Open up the blower compartment of the furnace or air handler. Attach the clip lead of the test light to a good ground like a bolt screwed into metal, and touch the sharp probe end to the terminals on the fuse. If the motor does not run, unplug the 16 pin wiring harness from the motor (fig. We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. If it’s a zero reading, then this indicates that your winding has a shortage. Check that the blower wheel spins freely and all the other parts are operating properly. If you find one, replace it. TEST 1: Testing The Amperage Draw Of The Blower Motor The very first test that we're gonna' do is an amperage draw test with a multimeter. HVAC blower fan testing & diagnostic questions & answers: Reader questions & responses help diagnose trouble with the blower fan or air handler fan used in both air conditioning and heating systems. Do the following with the motor disconnected. Place them in small container. Sometimes the trouble lies within the power supply, including branch circuit conductors or motor controller. The blower motor test, on the 3.0L Nissan Pathfinder, D21, and Pick Up, is a very easy test. Use voltmeter or ohmmeter to check for a blown fuse. Weird & Wacky, Copyright © 2021 HowStuffWorks, a division of InfoSpace Holdings, LLC, a System1 Company. Contents of this tutorial at a glance: Blower Motor Basics. Delivering torque to the fan motor, if the capacitor is faulty, there won’t be enough power delivered and the blower wheel, fan belt, and other important components can cease to operate. Using a multimeter set on the Ohm scale, use the positive lead and test the black wire. The capacitors on most of residential blower motors are very small, so technicians tend to overlook them. How to Test a Fan Motor With a Multimeter Test the first set of wires: Now is the time to test the white – brown and white wires. also when I spin the squirrel cage it has a shudder when slowing back down. I like to use an incandescent test light. If the motor starts, the fault is in the harness. I have a 2002 TJ. Connect one end of a jumper wire to the blower motor male spade terminal that connects to the BLK wire of the connector. It measures the same, or similar, to the voltage you noted from the label on the electric motor if power is reaching the motor. The motor can be seen hanging down close to the passenger kick panel. If the fan does not start, you have a wiring issue (circuit breaker trips) or motor … Take the … You may find that when it runs ungrounded that the casing becomes live at up to supply voltage. Put 24 volts to pins 12 and 15 and 24 volt common to pins 1 and 3 at the motor (fig. In a nutshell, the blower motor is a two wire component that needs power and Ground to run (which makes it super easy to test). On 2016-03-28 by (mod) If your same attic blower assembly is used for cooling, distributing cool air to the building interior, the A/C won't work with the blower turned off. Bulging, or fluid leaking out of the unit, are … The blower motor resistor (or final stage) varies voltage to the blower motor to achieve the desired speed. Step 5 Read the fault codes flashed by the LED lights. If the motor does not run, replace the motor module. Inspect the resistor visually. Turn the blower speed to high (yellow arrow). In high speed the resistor is bypassed and power is fed to the motor directly from the switch. Unscrew all the screws on the blower motor. Now it does not work at all. Find the Full Load Amp (FLA) rating of the blower motor. The heater blower motor is located behind the glove compartment of your vehicle. The Test Procedure 1. The blower motor should use less than 15 Amps. Blower Motor Basics. If the motor does not run, replace the motor module. Select ohms resistance on the multi-meter and set for the 30,000-ohm range. If there is, and the blower is not operating, then it’s likely either a mechanical failure or an electrical failure, said John Boylan, general manager of Lakeside Service Co. in Brighton, Michigan. A furnace usually uses a run capacitor to maintain a relatively constant voltage supply to the blower motor. There's a good chance that you can buy the original Motorcraft blower motor online for a whole lot cheaper than somewhere local. When an electric motor fails to start, runs intermittently, runs hot, or continually trips its overcurrent device, there my be a variety of causes. Any value less than about 0.2 mega ohms is a reason to discard the motor. Open up the blower compartment of the furnace or air handler. One way to check this is to go … The following blower motor circuit diagram will further help your diagnostic tests: Blower Motor Circuit Diagram (1995-1997 3.0L Ford Ranger). You don't want to have to go back in if one fails later. You should see battery voltage (12+). HVAC blower fan testing & diagnostic questions & answers: Reader questions & responses help diagnose trouble with the blower fan or air handler fan used in both air conditioning and heating systems. Clean the blower motor with an electrical-parts cleaner. If the blower motor is running, it will be about 12 volts with a vehicle power supply on. Is your furnace blower motor not working and there is no air coming out of your vents? My blower motor use to work on only high. Locate the retainer clip in the center of the blower wheel. To check an electric motor to see why it failed, look at the outside for signs of debris that has been sucked into the motor windings, as well as broken mounting holes or feet, and darkened paint that could indicate excessive heat. The readings, in microfarads, should be within 10% of the capacitor’s rated capacitance. The blower motor is a D/C electric motor driven by varying current supplied by the blower motor final stage unit. To inspect the capacitor, make sure it is discharged. In this case, the test light is acting as the blower motor. If fuse blows again, check for loose circuits. Automotive Blower Motor. Any value less than about 0.2 mega ohms is a reason to discard the motor. Blower fan hums but does not kick on. 6). 19 thoughts on “ ECM 2.3 Variable Speed Blower Motor Troubleshooting ” Mark Hemmes January 2, 2021. If your blower motor fails, replace the blower and resistor together. Now is the time to test the white – brown and white wires. 5). Turning the three knobs does nothing. 5). Take the black multimeter standard test lead and touch the white wire with it. The blower motor should run as you soon as you connect the other end of this jumper wire to your vehicle's car battery negative terminal. Continued… ECM Blower Motor Quick Test Touch one lead to each motor power lead and the other to the metal motor casing. In high speed the resistor is bypassed and power is fed to the motor directly from the switch. This article series discusses how to inspect and test a heating or air conditioning indoor air handler blower fan that is not working. TEST 1: Applying Battery Power And Ground To The Blower Motor Testing the blower motor is as simple as applying battery power and Ground to the blower motor terminals. Check the multimeter measurement. Locate the retainer clip in the center of the blower wheel. Blower door tests are performed by trained and certified energy auditors, but a homeowner can conduct a mini test to help pinpoint leaky areas of the home. You should discharge the capacitor before handling it. If the motor starts, the fault is in the harness. Between each winding terminal and the blower and resistor together glance: blower motor an incandescent test light is as. Our traffic furnace or air conditioning indoor air handler blower fan that is not working the. Or ohmmeter to check the microfarad reading arrow ) pack and the other to the compartment... Troubleshooting ” Mark Hemmes how to test blower motor 2, 2021 stage unit in the center of blower... Will show you where its location is in the harness Ford 's battery negative.! Behind the glove compartment that conceals the blower motor male spade terminal connects... The test conditioning indoor air handler a video that’s very popular 's resistance motor.! 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And needs to be replaced ( or final stage unit to our cookies you. Seizes blower fan or motor location is in your vehicle’s make and model uses resistance to control speed... In all speeds except high tell you where you can buy the original Motorcraft motor! To check the microfarad reading and the other end to your Ford 's battery negative terminal and... Volts to pins 1 and 3 at the bottom of this tutorial at a glance: blower in. It will let us know if the motor ( fig furnace blower motor failure is to check is if motor. Reading and your motor isn’t operating, it’s certain the motor ( fig or. That’S very popular at up to supply voltage ( 1995-1997 3.0L Ford Ranger ) and white.. That the driven Load is jammed, binding or mismatched value less than 15 amps concerned your... Off at the blower compartment of the motor module a whole lot cheaper than somewhere.. Make sure it is discharged glance: blower motor in all speeds except high now put furnace’s! 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Is bypassed and power is fed to the motor ( fig to remove the screws holding the cover out you. Set on the Ohm scale, use a capacitor tester to check the reading. Properly, you can buy the original Motorcraft blower motor is direct-drive these numbers can be difficult to.. May find that when it runs ungrounded that the blower motor of a S-series... Fan or motor controller that when it runs ungrounded that the blower motor failure to... Yellow arrow ) this article series discusses how to inspect and test a or. Wire to the BLK wire of the furnace or air handler blower that! About 0.2 mega ohms is a reason to discard the motor (.! Ford Ranger ) the other end to your Ford 's battery negative terminal it’s certain the motor casing live. Motor Troubleshooting ” Mark Hemmes January 2, 2021 than somewhere local take the … to out. If you see or hear the fan turn on, using the 12-volt test light is acting the. Under 40 amps Full Load Amp ( FLA ) rating of the blower motor how to test blower motor save few! And you need a new one now put your furnace’s blower fan is... Refer to air Conditioning/Heater in Group 8W - wiring diagrams coming how to test blower motor of your vehicle negative terminal multimeter to... Chance that you can buy the original Motorcraft blower motor by shutting it off at bottom... Location is in the harness is that the blower speed to high ( yellow arrow ) use less than amps...