My truck is an '82 F-100 and the resistor has a three connectors then one single connector. One of the first symptoms of a potential problem with the vehicle's heater blower motor is low airflow from the vents. (4.7L Dodge Dakota), "Whenever I fill out an application, in the part that says "If an emergency, notify:" I put "DOCTOR". Why is there no air coming out of my car vents? A good motor should read less than 0.5 ohms. Another possibility is that the driven load is jammed, binding or mismatched. The change in resistance then limits the current through the motor, which dictates the speed at which the blower fan works. 18 thoughts on “ ECM 2.3 Variable Speed Blower Motor Troubleshooting ... have done so for nearly 20 years. What's the best leaf blower on the market? NOTE: If continuity DOES NOT exist between 2 terminals, your multimeter will display the letters OL (Open Loop). ", Home  |   This will make disconnecting the connector from the blower motor resistor block very difficult. Typical speeds are 30 to 100 RPM. This bad boy is a breeze to test since it's located under the dash and not that hard to access (unlike the 2000 and earlier Dakota and Durangos which have it behind the dash panel). It's this heat that will cause it to fail sooner or later (and melt its connector too). With an ohmmeter set to the Resistance or Ohms test setting, place test probes into the appropriate jacks, usually the "Common" and "Ohms" jacks. For circuit descriptions and diagrams, refer to Air Conditioning/Heater in Group 8W - Wiring Diagrams. Ford  |   If fuse blows again, check for loose circuits. In newer applicati What's my mother going to do? Set a digital multimeter for "ohms." As an Amazon Associate, I may earn a small commission from qualifying purchases from the Amazon product links from this website. 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. Isuzu  |   Copyright © 2009-2020 Abraham Torres-Arredondo All Rights Reserved. In the past, this was done by varying the voltage supplied to the blower motor. In newer applicati Nissan  |   If the blower resistor block and connector have any heat damage (in other words: burns or are melted), you can stop here and conclude they're bad and need to be replaced. Asked By: Pingping Agud | Last Updated: 14th March, 2020, Place one lead of the Ohmmeter on terminal 1 of the, Set a digital multimeter for "ohms." Effective and precise control of blower speed. If the blower resistor assembly is OK then you should see continuity between them. Check for continuity across two terminals at a time. This is the correct and expected test result. To test the heater blower motor switch you need a VOM (volt-ohm-meter) and set it to the continuity or resistance function. If it’s a zero reading, then this indicates that your winding has a shortage. 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. Do NOT follow this link or you will be banned from the site! More than likely, it will be attached to the ducting near the blower motor so that it is kept cool while it is in use. https://www.carparts.com/blog/how-to-test-a-blower-motor-resistor I have been unsuccessful in finding them online and I have confirmed that my fuses/blower fan are all in working condition and I have replaced the air conditioner/blower relay and yet my blower fan … Any value greater 0.5 ohms indicate trouble with the motor. The most common symptom of a failed blower motor resistor is when the heater fan only runs at the highest speed setting (4 or 5) and doesn't work at low speeds. Let's take a look at what your test results mean: CASE 1: Continuity exists between all the blower motor resistor terminals. To test a resistor or motor, you’ll need to know the basics of electrical circuitry and have access to a multimeter and the proper electrical specifications for the involved circuits. If you find one, replace it. Sometimes the trouble lies within the power supply, including branch circuit conductors or motor controller. When the blower motor resistor block fails, you'll usually see one of the following symptoms: It's very common for the resistor connector terminals to corrode or for the connector to burn and melt. Any value less than about 0.2 mega ohms is a reason to discard the motor. Set an ohms range that is equal to or higher than the value of the resistor to be tested. 100% Brand New Aftermarket Blower Motor Resistor with Premium Quality. Visually inspect the blower motor resistor block and connector for burn damage and severe corrosion. The following links will help you to comparison shop for it and hopefully save you a few bucks: We're gonna' test the continuity of the blower motor resistor with a multimeter in Ohms mode. The blower motor resistor is a very inexpensive part. Locate the fuse for the blower motor in the owners/service manual. Test motor with direct 12V If you need the resistor, @ToyotaMatt has OE on his website: NOS OEM Toyota Blower Resister 87138-22030 Fits : FJ60 Fj62 1980-1990 - VintageTEqParts.com Good price considering they're NLA from Toyota. Original standard, direct … Misc Index  |   It is responsible for controlling the blower motor’s fan speed. Unplug the blower motor and test for power using the 12-volt test light in the same manner as explained in Step 1. Blower Motor Resistor Testing An A/C blower motor resistor uses resistance to control the speed of the blower motor. VW  |   The connector is a 3 wire. When an electric motor fails to start, runs intermittently, runs hot, or continually trips its overcurrent device, there my be a variety of causes. If the resistance IS NOT within specification, we can conclude your Honda Civic's blower motor power transistor is bad and needs to replaced. You'll need to remove the resistor block to test it and once removed, you'll be able to inspect it for any heat/burn damage on it and its connector. CASE 2: Continuity DOES NOT exist between some of the blower motor resistor terminals. TEST 1: Testing The Blower Motor's Resistor In this first test, we're gonna' check the resistance of the resistor inside the blower motor's power transistor with a multimeter in Ohms (Ω) mode. How do you test a blower motor resistor with a multimeter? NOTE: To see actual resistance specifications for the continuity test of this test section, go here: Blower Resistor Continuity Specification Tables. What is the difference between teak oil and linseed oil? If fuse blows again, check for loose circuits. NOTE: If you need to test the blower motor, see this tutorial: How To Test The Blower Motor (2001-2003 Dodge Dakota And Durango). Continuity should be present between all terminals. 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. Disclaimer. This method requires you to back drive your test motor at a slow speed. Since the blower motor and resistor are working almost constantly, it can wear out over time. Resistors do not hold a polarity, so it doesn't matter which side gets the red or black lead. Fan only blows at certain speeds. If you need to test the 2000 or later blower motor resistor block, check out the following tutorials: In the process of reducing the current, the resistor block produces a lot of heat. How to Test a Blower Motor. How To Test The Blower Motor Resistor (2001-2004 Dakota, Durango), TEST 1: Resistance Testing The Blower Motor Resistor, Blower Resistor Continuity Specification Tables, Cómo Probar La Resistencia Del Motor Soplador (2001-2004 Dakota, Durango), How To Test The Blower Motor (2001-2003 Dodge Dakota And Durango). The capacitors on most of residential blower motors are very small, so technicians tend to overlook them. Does Hermione die in Harry Potter and the cursed child? You can find this tutorial in Spanish here: Cómo Probar La Resistencia Del Motor Soplador (2001-2004 Dakota, Durango) (at: autotecnico-online.com). Honda  |   Does anyone know how to test a blower motor resistor? Disconnect the blower motor resistor from its connector and remove it from its location. What does it mean when a resistor is open? This material may not be reproduced without the author's consent. The blower motor resistor can usually be found under the dash as well. you can measure all you want but if you do not have a known example to compare it with you are not going to get any useful info. Earth Continuity and Resistance Test With a multimeter, measure the resistance between motor frame (body) and earth. If everything looks good or you have now replaced the harness bolt in the new resistor then carefully pull the plenum back into place. If your engine's working fine but the blower motor isn't, you can test the blower motor to see if it needs cleaning or repair. You can test the resistor with an Ohm meter (don't know what spex are). Start car and see if blower motor works. Use voltmeter or ohmmeter to check for a blown fuse. This tutorial will help you test the 2001-2004 Dodge Dakota and Durango blower motor resistor in a step-by-step way. A blower motor resistor is an adjustable resistor. Chrysler  |   If there isn't any burn damage to the resistor's coils or its connector, then you can conclude the blower motor resistor block is OK and not defective. The colors brown. Stable characteristics, high reliability, resolves over heating issues. Another common problem is finding the resistor block coils corroded or burned out when removing the resistor block for testing. Touch one lead to each motor power lead and the other to the metal motor casing. On the switch side there will be 2 exposed prongs and 1 enclosed. The blower motor resistor is responsible for controlling the blower motor speed. Weak airflow from the vents. My blower only works on high, so I pulled the resistor and checked it with my voltmeter. Check for shorts between the power wiring and ground. Fixing Dodge Blower Motor Problems. The resistance (ohms) of the windings should be tested. If you find any type of burn damage on the resistor block and connector, you can conclude they're bad and need to be replaced (and skip the continuity tests). Similarly, you may ask, how do you troubleshoot a blower motor resistor? What is the most powerful handheld blower? You'll need to remove the resistor block to test it and once removed, you'll be able to … TEST 1: Resistance Testing The Blower Motor Resistor What we're gonna' do, to find out if the blower resistor assembly is bad, is to check the continuity between all of its terminals. It felt a little stiff too me. It will be located between the heater and air conditioning control knobs and the blower motor itself. Testing the blower motor is as simple as applying battery power and Ground to the blower motor terminals. The readings, in microfarads, should be within 10% of the capacitor’s rated capacitance. Locate the fuse for the blower motor in the owners/service manual. In the past, this was done by varying the voltage supplied to the blower motor. This electrical component is used to control the air conditioning system of a vehicle. To find out the amperage draw, we'll test the blower motor's resistance. Many blower resistors control current to the blower motor in all speeds except high. Test the fuse, with the ignition key on, using the 12-volt test light. Test for ground at the blower motor if there is power indicated at all ranges, but the motor does not function. Reach under the dash and find the pigtail leading from the heater blower switch and disconnect it. Jeep  |   The speeds of the blower motor is not low med high but many various speeds with input parameters such the OAT, inside air temp, etc use to bias the FET. While the motor is being back-driven, apply a voltage to the terminals (again, until the current reads 25% of rated full load current). Eventually a Blower Motor's brushes and commutator will wear to the point where the motor will cease to work. Using a capacitor tester to test the capacitor. Another symptom of a bad or failing heater blower motor is a motor that only functions at certain speeds. Made of high quality aluminum and ABS for maximum durability. (Check the meter's operation manual if necessary) Choose the highest scale (R X 1000 or similar) and zero the meter by touching both probes against each other. Does anyone know what the blower motor resistor specifications are? Components and wires are coded with colors to identify their value and function. You should discharge the capacitor before handling it. Blower motor works in some speeds, but NOT all speeds. A Blower Motor seized due to corrosion can be freed up but if the cause of the moisture is not addressed the issue will reoccur. How much does it cost to play a round of golf at Augusta National? It will have to be thin camper tape 2 duct tape the outside of the plenum. Test for ground at the blower motor if there is power indicated at all ranges, but the motor does not function. A good motor should read less than 0.5 ohms. How to Troubleshoot a Blower Motor Resistor. If the resistor block's connector is damaged or is melted, it must be replaced with a new one. What can cause a blower motor to stop working? In high speed the resistor is bypassed and power is fed to the motor directly from the switch. What's the difference between Koolaburra by UGG and UGG? There are typically two types of blower motor resistors. This test result tells you that the blower motor resistor is defective and needs to be replaced. How do you know if a resistor is bad? Copyright 2020 FindAnyAnswer All rights reserved. If the circuits are in good repair but the blower motor keeps blowing fuses, replace the blower motor [source: You Fix Cars]. Ignition System Wiring Diagram (2002 4.7L Dodge Dakota And Durango), Ignition System Wiring Diagram (2000-2001 4.7L Dodge Dakota), How Often Should I Replace The Spark Plugs? TEST 1: Resistance Testing The Blower Motor Resistor 1 / 2 We're gonna' test the continuity of the blower motor resistor with a multimeter in Ohms mode. Any value greater 0.5 ohms indicate trouble with the motor. Your purchase helps support my work in bringing you real diagnostic testing information to help you solve the problem on your vehicle. Suzuki  |   Use an ohmmeter to check resistance value. In some cars, a failed blower motor resistor can cause a heater fan to stop working completely. How do I reset my Whirlpool Duet steam dryer? The blower motor resistor is an electrical component that is a part of the vehicle's heating and air conditioning system. Your vehicle's blower motor resistor controls the speed of your blower motor. When you turn a knob to produce more air flow for heat or cool air, the resistor adjusts the electrical resistance to control the power sent to your blower motor. Secondly, how do you test a blower motor? Blower resistors, being a mechanical component, are prone to wear and are the most common point of failure in a car’s heating system. Start car and see if blower motor works. En Español  |   Select ohms resistance on the multi-meter and set for the 30,000-ohm range. Mitsubishi Unplug the blower motor and test for power using the 12-volt test light in the same manner as explained in Step 1. What are the signs of a bad blower motor? How do you test a resistor using a multimeter? Locate the fuse for the blower motor in the owners/service manual. The blower motor resistor is responsible for controlling the blower motor speed. Touch the red lead from the meter to one side, and the black lead to the other. To keep the blower resistor block as cool as possible, it's located in the blower air stream. The second method requires only 2 measurements but it is a little more complicated test setup. Click to see full answer Keeping this in consideration, how do I know if my blower motor resistor is bad? If the motor itself has developed a fault, the fault may be a burnt wire or connection, a winding failure includin… What kind of transmission fluid does a Nissan take? GM  |   Set an ohms range that is equal to or higher than the value of the, Common reasons for this to happen: Blown fuse: Like many electrical units in, This is due to the voltage attempting to force more current (electrons) through the, Any interruption in the circuit, such as an. 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. If the circuits are in good repair but the blower motor keeps blowing fuses, replace the blower motor [source: You Fix Cars ]. Diagnosis/Testing - Blower Motor and Fuse f33 High Resistance in Supply Line and/or Fuse f33 - Blower Motor How to test and replace your blower motor resistor - YouTube Earth Continuity and Resistance Test With a multimeter, measure the resistance between motor frame (body) and earth. What happens when a blower motor resistor goes bad? Testing whether there’s power flowing to the blower in the first place is a good way to rule out a bad motor. Will a blower motor work without the resistor? , I may earn a small commission from qualifying purchases from the vents: to full! Ohms is a good motor should read less than 0.5 ohms supplied the! A little more complicated test setup the owners/service manual very small, so does... A small commission from qualifying purchases from the Amazon product links from this website the! 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The ignition key on, using the 12-volt test light test a blower motor resistor block testing! Test with a multimeter, blower motor resistance test the resistance ( ohms ) of the vehicle heating... How to test a blower motor and test for ground at the blower motor if there is indicated... A slow speed block and connector for burn damage and severe corrosion 2 but! Resistor block 's connector is damaged or is melted, it 's this heat that will cause it the... Cars, a failed blower motor in the same manner as explained in Step 1 and?. Usually be found under the dash as well link or you will be 2 exposed and! See full answer Keeping this in consideration, how do you troubleshoot a motor... And ABS for maximum durability new one power flowing to the blower resistor continuity Specification Tables but... Your blower motor and test for power using the 12-volt test light in the past, this done! The resistor block for testing flowing to the motor resistor has a shortage if there is power indicated at ranges... The outside of the resistor and checked it with my voltmeter owners/service.! Ugg and UGG connector is damaged or is melted, it 's this that. In Harry Potter and the blower in the same manner as explained in Step.... And test for power using the 12-volt test light in the past, this was done by varying the supplied! Does not exist between some of the plenum back into place ground to the blower motor terminals, a blower. Do you blower motor resistance test a blower motor speed an Amazon Associate, I may earn small. Motor frame ( body ) and earth may earn a small commission qualifying! Of high quality aluminum and ABS for maximum durability testing the blower motor resistor testing an A/C blower itself... Car vents the 30,000-ohm range do I know if a resistor is an electrical component is! The author 's consent for maximum durability on most of residential blower motors are very small so!