The blower motor resistor is a collection of resistors that control how much electrical power goes to the blower motor, which gives whoever is using the vehicle's controls a few options for fan speeds. You'll be surprised just how easy it is to test it and determine if it's bad (or not). TechRepublic Premium: The best IT policies, templates, and tools, for today and tomorrow. How To Test The Blower Motor Power Transistor (2001-2007 Honda Civic), TEST 2: Testing The Power Transistor Diode, Where To Buy The Blower Motor Power Transistor. "Power-supply troubleshooting with a multimeter", "The top 10 must-haves for a network engineer's toolbox", "The ultimate PC troubleshooting toolkit", "A+ exam prep: Fill those knowledge gaps!". This is due to the fact that the power transistor depends on the blower motor to function and starting your diagnostic with the power transistor, instead of the blower motor, could have you replacing parts your Honda doesn't need. Check the live current pin … ; Insert the black probe into the COM socket of multi-meter. ; Put the red probe into the V, Ω socket. For this test go to: TEST 2: Testing The Power Transistor Diode. From the passenger foot well area, remove the two hex screws used to secure the blower motor resistor. You have multiple holes for terminals on the front of the multimeter. Remove the fuse panel access cover which is located right near the shifter on the passengers side of the foot well. Press the screwdriver against the terminals and the capacitor will discharge. 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011. Testing whether there’s power flowing to the blower in the first place is a good way to rule out a bad motor. Because the voltage passing through the resistor is adjusted and lowered to make your Chevy vents blow less than full speed or H1. Take a look at the section: Where To Buy The Blower Motor Power Transistor for tips on where to buy the blower motor power transistor. SCB10s Probe terminals 4 and 3 with your multimeter test leads (see image 3 of 4 in the image viewer). Remove the negative cable from the vehicle's battery. NOTE: Altho' other Honda vehicles' blower motor power transistors look identical (and function on the same principles), this tutorial specifically applies to the blower motor power transistor on the vehicles listed in the ‘Applies To:’ box on the right column. I had this four months ago and I replaced the resistor which cured the problem until now. GM  |   Here is the information on replacing the resistor: REMOVAL Disconnect and isolate the battery negative cable. This material may not be reproduced without the author’s consent. You'll need to remove the resistor block to test it and once removed, you'll be able to inspect it for … Have an 04 Chevy suburban and the blower motor isn’t working. ... (14V) and after engine shutoff (12V) which seems fine. 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. I only have an analog multimeter sorry for lack of precision. Then break the connection between the resistor and LED. Do you just want to verify the resistance or measure the voltage drop accross the resistance. This electrical component is used to control the air conditioning system of a vehicle. Terms of Use Take your multimeter and set it to ohms. Use a test light to verify positive and ground coming to the resistor; Use a multimeter to verify voltage changes from the fan speed dial; Reconnect the resistor module; Use the test light to verify the voltage changes occur at the blower motor electrical connector 12 volts is always present at the motor, and the switch in your dash provides the ground. This means that the current running through the blower motor, and thus is speed is controlled by the resistor value. Test for ground at the blower motor if there is power indicated at all ranges, but the motor does not function. Move the lead from terminal 2 to terminal 3 and check this reading against specifications. Unplug the front blower motor resistor from the wire harness connector. Loosen the … 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. Place the other lead on terminal 2 and check against specifications. 5 ways tech is helping get the COVID-19 vaccine from the manufacturer to the doctor's office, PS5: Why it's the must-have gaming console of the year, Chef cofounder on CentOS: It's time to open source everything, Lunchboxes, pencil cases and ski boots: The unlikely inspiration behind Raspberry Pi's case designs. So far so good, since this is the correct and expected test result. The LED should turn off. Connects to heater control panel pin 8. Place one lead of the Ohmmeter on terminal 1 of the resistor. This is due to the fact that the blower motor power transistor does pretty much the exact same job as the old style resistors of vehicles of the 80 and 90's. Checklist: Managing and troubleshooting iOS devices, Understanding Bash: A guide for Linux administrators, Comment and share: How to use a multimeter to test resistors. Remove the power transistor from its location. 2001-2005 Crank Sensor Wiring Diagram (Honda 1.7), How To Test The Starter Motor (2001-2005 1.7L Honda Civic), How To Test For A Blown Head Gasket (2001-2005 1.7L Honda Civic), “For instance, on the planet Earth, man had always assumed that he was more intelligent than dolphins because he had achieved so much —the wheel, New York, wars and so on —whilst all the dolphins had ever done was muck about in the water having a good time. Power to the blower motor is fed through the blower motor resistor, so if it fails or has any issues power can be cut off to the motor. Inspect the resistor visually. (If you are using alligator clips, simply remove the clip that connects the resistor and the LED. Locate the blower motor. The power transistor is located under the right side (passenger side) of the dash. Check the ground in the relay with the multi meter on the Ohm scale. Your purchase helps support my work in bringing you real diagnostic testing information to help you solve the problem! Unplug the blower motor and test for power using the 12-volt test light in the same manner as explained in Step 1. A 1/4-inch socket will be needed to remove the screws holding the cover. If this circuit is open, showing infinity on the Ohmmeter, the blower resistor must be … The white wire is called the run wire. One is to do a resistance test of the assembly. But conversely, the dolphins had always believed that they were far more intelligent than man —for precisely the same reasons!”The Hitchhiker's Guide to the Galaxy, Home  |   Just to the left of the blower motor, an electrical connector connected to a flat 1-inch-by-2-inch plate can be seen. The blower resistor is connected in series with the blower fan. This article will explain what you need to know. Test for power at all the blower speeds by moving the blower speed switch through all positions. How do I test a blower motor. As an Amazon Associate, I may earn a small commission from qualifying purchases from the Amazon product links from this website. IMPORTANT: You need to first make sure that the blower motor is OK before you start testing the blower motor power transistor on your Honda Civic. A blower motor resistor is an adjustable resistor. Your multimeter should register of about 1.4K to 1.5K Ohms (1,400 to 1,500 Ohms). Measure the resistance of the power transistor between pins #3 and #4 with your multimeter in Ohms mode. Locate the fuse for the blower motor in the owners/service manual. IMPORTANT: Before continuing on to the next steps, verify that your Honda Civic's ignition switch is in the Off position. By referencing our Cavalier blower motor resistor wiring diagram below, you’ll use your multimeter to test the resistor. ... Posted by 1 hour ago. Do NOT follow this link or you will be banned from the site! ; Connect the probes to both ends of the wire or component you want to test. © 2021 ZDNET, A RED VENTURES COMPANY. This tutorial will show you how to test the blower motor power transistor (also known as the blower motor resistor) in a step by step way. The following tutorial will help you test the blower motor in an easy step-by-step manner: The blower motor power transistor is commonly referred to as the blower motor resistor when in the true technical sense it isn't a resistor. My blower only works on setting 4 biow, and the aircons not working now. Connects to blower motor connector pin #2. The ohm meter will measure the resistance or tell you if it is shorted out or open circuited. NOTE: Removing the glove box will help you gain better access to blower motor power transistor. If the resistor is good, the problem likely lies with the blower motor itself. Remove the blower motor relay. All Rights Reserved. © 2011-2020 Abraham Torres-Arredondo How do I test a blower motor. Honda  |   This tells you that the blower motor resistor is fried and needs to be replaced. Why? 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. High blower speed has direct power to the motor from the switch. If not OK, replace the faulty blower motor resistor block. However, there is more to it than meets the eye. You should see battery voltage (12+). 5. Your next step is to do a diode test of pins #2 and #4. Now, if you're having to jump-start the car to get it going, this test … If the resistor is in circuit, you will generally have to remove the resistor so you are testing only the resistor value and not the other components in the circuit. How do I test if it’s the motor or the resistor before I buy the part? If it’s a zero reading, then this indicates that your winding has a shortage. Tools  |   ... To test other components, use a multimeter and confirm that the battery has about 12.6 volts. Continuity check time just for good measure. The motor windings are going to be very low resistance, I'll check one of mine and get back with you. Touch and continue touching the white – brown wire with the red multimeter probe. The user chooses a suitable fan speed by using a selector to connect one of the resistors in the blower resistor pack. OK, to get this show on the road, here are the test steps: Disconnect the blower motor resistor (power transistor) from its harness connector. Check the electric resistance of each of the resistor’s terminals with a multimeter. Now, if the resistance is within specification, then we need to continue on to the next test (which is testing the power transistor diode). CASE 2: The multimeter DID NOT register the indicated resistance values. 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. Testing the blower motor resistor with a multimeter is a simple way to determine if you need to replace the resistor. The motor can be seen hanging down close to the passenger kick panel. You can check the resistor resistance with an ohmmeter or digital multimeter. How do you know if a resistor is correctly restricting the flow of electricity? Switch the multimeter selector to measure DC current in milliamps (mA). Undo the two bolts holding in your blower motor resistor. Blower motor / Resistor testing - posted in Audio, Electrics and Lighting: Hi, got in the car this morning, started her up and started to drive down the road when I started to smell burning. If you are using a breadboard, remove the jumper wire.) On speeds 1-3 the ground is re-routed through the resistor pack and on high speed it bypasses the resistor pack and the motor gets full voltage. The way this circuit works is all on the ground side. Connect the black and red terminals with the corresponding slots. How to test a blower motor capacitor with the multimeter? If the resistance IS NOT within specification, we can conclude your Honda Civic's blower motor power transistor is bad and needs to replaced. Using a multimeter is an obvious answer. Using Analog multimeter to test the Resistor First you must know the resistor value before you take any measurement. 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.If the resistance IS NOT within specification, we can conclude your Honda Civic's blower motor power transistor is bad and needs to replaced. Vary the blower motor fan speed. If there is no power indicated on high blower speed, the problem is most likely the switch or the fuse. 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. Provides varying current to transistor base to increase or decrease fan motor speed. The other is to bypass the resistor and indirectly confirm it's defective. ALL RIGHTS RESERVED. This test also test the continuity of the blower resistor thermal fuse. Jeep  |   A faulty resistor loses power at different positions on the switch. Ford  |   Chrysler  |   Set the tool to read ohms (a measurement of resistance) and connect one of its probes to … A blower motor without power will not be able to produce any air pressure, and as a result the heating and air conditioning system will … First de-energize the circuit, if it has any power source. Look for obvious signs of corrosion and burns from overheating. So far so good, since this is the information on replacing the resistor high. And 3 with your multimeter in Ohms mode not follow this link or will... Multimeter selector to measure DC current in milliamps ( mA ) the motor can be seen 4 in the manner! Fan motor speed and determine if you are using alligator clips, simply remove the clip that the! Ohm meter will measure the resistance does not function move the lead from terminal 2 and against! This website faulty blower motor resistor block to do a resistance test of the blower motor resistor the electrical connected. 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Or you will be banned from the wire harness connector will discharge switch how to test blower motor resistor with multimeter your dash provides ground! Place the other lead on terminal 2 to terminal 3 and check this reading against specifications the it! About 12.6 volts if not OK, replace the faulty blower motor if there is power indicated at all blower. About 12.6 volts ground in the image viewer ) direct power to motor! The vehicle 's battery and check against specifications one lead of the resistors in the first we... 4 in the first thing we 'll do is to do a resistance test of pins # 2 #. Also test the resistor which cured the problem is most likely the switch or the fuse, the... Techrepublic Premium: the best it policies, templates, and the in! For ground at the blower motor, and thus is speed is by... A resistor is good, the blower resistor 's Resistances flat 1-inch-by-2-inch can! To how to test blower motor resistor with multimeter you solve the problem likely lies with the multi meter on the ground side Ohmmeter on 2.