19 thoughts on “ ECM 2.3 Variable Speed Blower Motor Troubleshooting ” Mark Hemmes January 2, 2021. Any value less than about 0.2 mega ohms is a reason to discard the motor. The white wire is called the run wire. Blower Motor Basics. You may find that when it runs ungrounded that the casing becomes live at up to supply voltage. An A/C blower motor resistor uses resistance to control the speed of the blower motor. 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. Perhaps your blower motor has burnt out and you need a new one. To find out the amperage draw, we'll test the blower motor's resistance. The blower motor is a D/C electric motor driven by varying current supplied by the blower motor final stage unit. 6). Now put your furnace’s blower fan to the test. 5). 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. Open up the blower compartment of the furnace or air handler. 6). Any value less than about 0.2 mega ohms is a reason to discard the motor. If the motor itself has developed a fault, the fault may be a burnt wire or connection, a winding failure including insulatio… Step 5 Read the fault codes flashed by the LED lights. To inspect the capacitor, make sure it is discharged. Take your multimeter and set it to ohms. If the motor is direct-drive these numbers can be difficult to read. Take the … A furnace usually uses a run capacitor to maintain a relatively constant voltage supply to the blower motor. A 1/4-inch socket will be needed to remove the screws holding the cover. 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. 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. 2. 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 heater blower motor is located behind the glove compartment of your vehicle. 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. 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. We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. I have a 2002 TJ. €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! If the motor does not run, unplug the 16 pin wiring harness from the motor (fig. A repair manual can tell you where its location is in your vehicle’s make and model. If you have a reading and your motor isn’t operating, it’s certain the motor is the problem and needs replacing. 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. I have a 2006 Bard Geothermal . Start by turning the furnace off, turn your thermostat to “fan only,” and wait a few minutes. 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