Locate the fuse for the blower motor in the owners/service manual. Test for power at all the blower speeds by moving the blower speed switch through all positions. 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. 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. This electrical component is used to control the air conditioning system of a vehicle. The first thing we'll do is to check continuity of each resistor that makes up the blower resistor assembly. Your multimeter should register of about 1.4K to 1.5K Ohms (1,400 to 1,500 Ohms). 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. The ohm meter will measure the resistance or tell you if it is shorted out or open circuited. SCB10s (If you are using alligator clips, simply remove the clip that connects the resistor and the LED. You should see battery voltage (12+). 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 How do I test if it’s the motor or the resistor before I buy the part? 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011. 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. 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. Assuming you are measuring a resistor with the color of – yellow, purple, black and gold -from the calculation it is a 47 ohms resistor with 5% tolerance. The power transistor is located under the right side (passenger side) of the dash. There are two basic ways of testing the blower motor resistor assembly. However, there is more to it than meets the eye. The way this circuit works is all on the ground side. Your next step is to do a diode test of pins #2 and #4. How to test a blower motor capacitor with the multimeter? All Rights Reserved. Tools  |   If you are using a breadboard, remove the jumper wire.) Testing the blower motor resistor with a multimeter is a simple way to determine if you need to replace the resistor. Have an 04 Chevy suburban and the blower motor isn’t working. 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. 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. Your purchase helps support my work in bringing you real diagnostic testing information to help you solve the problem! 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. © 2021 ZDNET, A RED VENTURES COMPANY. ; Insert the black probe into the COM socket of multi-meter. "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!". Provides varying current to transistor base to increase or decrease fan motor speed. This tells you that the blower motor resistor is fried and needs to be replaced. This material may not be reproduced without the author’s consent. 5. Set the tool to read ohms (a measurement of resistance) and connect one of its probes to … Ford  |   Testing whether there’s power flowing to the blower in the first place is a good way to rule out a bad motor. This article will explain what you need to know. If you want to test a blower motor capacitor of yours, make sure that you discharge it with a screwdriver before you begin the test. The resistance (ohms) of the windings should be tested. Using Analog multimeter to test the Resistor First you must know the resistor value before you take any measurement. OK, to get this show on the road, here are the test steps: Disconnect the blower motor resistor (power transistor) from its harness connector. If the resistance IS NOT within specification, we can conclude your Honda Civic's blower motor power transistor is bad and needs to replaced. TechRepublic Premium: The best IT policies, templates, and tools, for today and tomorrow. Connects to blower motor connector pin #2. 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. Loosen the … Honda  |   Let's take a look at what your test results mean: CASE 1: The multimeter indicated the indicated resistance values. Remove the blower motor relay. TEST 1: Checking The Blower Resistor's Resistances. I had this four months ago and I replaced the resistor which cured the problem until now. So far so good, since this is the correct and expected test result. CASE 2: The multimeter DID NOT register the indicated resistance values. How do I test a blower motor. ; Put the red probe into the V, Ω socket. Using a multimeter is an obvious answer. The user chooses a suitable fan speed by using a selector to connect one of the resistors in the blower resistor pack. ; Set the dial of the multimeter to resistance mode Ω.If it has many ranges, set the dial to the minimum range. First de-energize the circuit, if it has any power source. Then break the connection between the resistor and LED. Check the electric resistance of each of the resistor’s terminals with a multimeter. Press the screwdriver against the terminals and the capacitor will discharge. IMPORTANT: Before continuing on to the next steps, verify that your Honda Civic's ignition switch is in the Off position. 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. A 1/4-inch socket will be needed to remove the screws holding the cover. Remove the power transistor from its location. Now, if you're having to jump-start the car to get it going, this test … As an Amazon Associate, I may earn a small commission from qualifying purchases from the Amazon product links from this website. The other is to bypass the resistor and indirectly confirm it's defective. Place the other lead on terminal 2 and check against specifications. ... Posted by 1 hour ago. 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 … Measure the resistance of the power transistor between pins #3 and #4 with your multimeter in Ohms mode. Normally if a resistor fail they will either increase in value or open up at all (open circuit). Chrysler  |   By referencing our Cavalier blower motor resistor wiring diagram below, you’ll use your multimeter to test the resistor. Check the ground in the relay with the multi meter on the Ohm scale. If not OK, replace the faulty blower motor resistor block. My blower only works on setting 4 biow, and the aircons not working now. The blower resistor is connected in series with the blower fan. 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. Inspect the resistor visually. Just to the left of the blower motor, an electrical connector connected to a flat 1-inch-by-2-inch plate can be seen. Your multimeter should register a resistance of about 0.2 to 0.3 Ohms ( Ω ). Place one lead of the Ohmmeter on terminal 1 of the resistor. A faulty resistor loses power at different positions on the switch. 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. You can check the resistor resistance with an ohmmeter or digital multimeter. NOTE: Removing the glove box will help you gain better access to blower motor power transistor. Connects to heater control panel pin 8. 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. Checklist: Managing and troubleshooting iOS devices, Understanding Bash: A guide for Linux administrators, Comment and share: How to use a multimeter to test resistors. From the passenger foot well area, remove the two hex screws used to secure the blower motor resistor. One is to do a resistance test of the assembly. High blower speed has direct power to the motor from the switch. Here is the information on replacing the resistor: REMOVAL Disconnect and isolate the battery negative cable. The motor can be seen hanging down close to the passenger kick panel. Connect the black and red terminals with the corresponding slots. If this circuit is open, showing infinity on the Ohmmeter, the blower resistor must be … For this test go to: TEST 2: Testing The Power Transistor Diode. Vary the blower motor fan speed. Take your multimeter and set it to ohms. 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  |   Look for obvious signs of corrosion and burns from overheating. Test for ground at the blower motor if there is power indicated at all ranges, but the motor does not function. How do you know if a resistor is correctly restricting the flow of electricity? Undo the two bolts holding in your blower motor resistor. ALL RIGHTS RESERVED. How do you know if a resistor is bad? Take the black multimeter standard test lead and touch the white wire with it. Unplug the front blower motor resistor from the wire harness connector. ; Connect the probes to both ends of the wire or component you want to test. Move the lead from terminal 2 to terminal 3 and check this reading against specifications. 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. Jeep  |   If power is supplied to blower motor through the speed switch and blower motor resistor: Disconnect the electrical connector at the blower motor. I only have an analog multimeter sorry for lack of precision. If it’s a zero reading, then this indicates that your winding has a shortage. Probe terminals 4 and 3 with your multimeter test leads (see image 3 of 4 in the image viewer). Remove the fuse panel access cover which is located right near the shifter on the passengers side of the foot well. Do NOT follow this link or you will be banned from the site! You'll need to remove the resistor block to test it and once removed, you'll be able to inspect it for … You have multiple holes for terminals on the front of the multimeter. If the resistor is good, the problem likely lies with the blower motor itself. You'll be surprised just how easy it is to test it and determine if it's bad (or not). This test also test the continuity of the blower resistor thermal fuse. Continuity check time just for good measure. 12 volts is always present at the motor, and the switch in your dash provides the ground. Unplug the blower motor and test for power using the 12-volt test light in the same manner as explained in Step 1. This means that the current running through the blower motor, and thus is speed is controlled by the resistor value. How do I test a blower motor. Locate the blower motor. Disclaimer. 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. Remove the negative cable from the vehicle's battery. ... To test other components, use a multimeter and confirm that the battery has about 12.6 volts. 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. Download Ebook How To Test 2004 Honda Pilot Blower Motor Resistor ... No further testing is required, since this multimeter test result eliminates the alternator on your Honda Civic as bad. The LED should turn off. 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. Because the voltage passing through the resistor is adjusted and lowered to make your Chevy vents blow less than full speed or H1. ... (14V) and after engine shutoff (12V) which seems fine. Why? Terms of Use If this circuit is open, showing infinity on the Ohmmeter, the blower resistor must be replaced. Do you just want to verify the resistance or measure the voltage drop accross the resistance. 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. Check the live current pin … 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. 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. When testing a resistor, the multimeter is passing a known amount of electrical current through the resistor and then measuring the amount of current that actually makes it through. A blower motor resistor is an adjustable 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. © 2011-2020 Abraham Torres-Arredondo 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. 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You real diagnostic testing information to help you gain better access to blower motor resistor: Disconnect.