How to test can bus wiring with multimeter

How to test can bus wiring with multimeter. With the wiring test, it is pos­si­ble to deter­mi­ne line short-cir­cuits, line breaks, the bus ter­mi­na­ti­on, the loop resis­tance of the CAN line and the CAN power sup­p­ly line and the over­all line length. You have to check every wire this way. Test the voltage at the diagnostic connector between pins A & C 2. Check if there is 5v voltage on the USB port. Jul 15, 2023 · To test an electric guitar without an amp, you’ll need a 9-volt battery, a guitar cable, and a multimeter. If they pass the test, turn off the power and open up the switch, recheck the wiring, and replace the switch if necessary. . Next, connect the guitar cable to the guitar and the multimeter. April 30, 2020 ·. In this video we look at how to test CAN high and CAN low wiring with a multimeter, and show you IN-DEPTH all the different measurements you should be taking when using resistance to check the can bus network. Local Interconnect Network (LIN) bus communication is becoming more common on modern CAN Bus-equipped vehicles. How to test can bus wiring with multimeterHow to use multimeter to check car wiring। कार की वायरिंग चेक Begin the testing process by disconnecting the termination resistors at both ends of the CAN Bus network. Use a screwdriver to unscrew the lid on the box and open it. Posted by 1 year ago. Measure resistance from CAN HI to Ground and from CAN LOW to Ground. After you pull a fuse, check the multimeter to see if the reading changes. Dec 2, 2019 · To check your network’s termination, disconnect the CAN interface’s D-sub 9 pin from the network and measure resistance through the cable by placing a digital multimeter / ohmmeter between pin 2 and 7. Test the voltage at the diagnostic connector between pins A & D Mar 13, 2024 · Step 6: Turn On The Ignition Key. Understanding the network topology is like knowing the road map of your car's communication system. Use a CAN breakout box to connect to it. The DC Voltage setting will enable you to test small electronic ciruits, indicator lights and batteries. What I want to accomplish: provide a free educational source for anyone interested in learning about automobiles. Jan 19, 2015 · If all you have is a bunch of multimeters all you will get is whether the cable works or not. Mar 8, 2022 · This is so when you turn the connector over you know which terminal to test from. Web how to test can bus with a multimeter. Oct 28, 2023 · This can bus diagnostics test is very easy and simple when done correctly. This step temporarily removes termination from the network. enovationcontrols. Wiring garage multimeter hemmingsHow to test can bus wiring with multimeter . If you fail to do, a component connected to the CAN bus line may be broken. Check if the USB port is hot. In this article, we’ll discuss the basics of using a multimeter to test doorbell wires. Values can dif­fer, then you should look for breaks and bad con­nec­tions. This means that the ECU is getting power and is functioning properly. This handy sheet shows steps to test the bus with multimeter: termination resistance, CAN HIGH & LOW voltages Oct 10, 2023 · 3. Discove Wiring termination instruction and Bus check multimeter mindset mechanic Transmitter temperature 20ma multimeter test Can bus quick check with multimeter Installing wiring garage multimeter hemmingsBus test resistance check multimeter Finding can bus faults with multimeterThe wiring diagram of the 6-bus test system. Fixing three of the more common problems that can befall a CAN bus system include: Check over the CAN bus wiring. Step 4. One of the ways to test the CAN bus is by measuring its resistance using a multimeter. Help technicians decide a new Electronic Control Unit (ECU)/electronic components is needed. a motor controller, are still attached but powered down. Touch the black probe to the terminal on one side of the component you’re measuring, and the red probe to the terminal on the other side of the component. Once the appropriate setting has been chosen, connect the multimeter leads to both ends of the wire using alligator clips. It will help you determine which one is hot. Set your multimeter to measure AC voltage (200 volts). Check Details Archivi downloads. As a result, you won't be able to get your car going and you'll need to replace the relay. This will be the terminal used for testing. If the multimeter readings show a significant voltage drop or fluctuation, it may indicate a problem with the CAN bus wiring or a faulty ECU. 5 VDC Less than 700 MV: A- is shorted to the shield, potentially by a stretched or crushed wire. All the wire junctions should have a strong solder and splices that are secure. Further guidance. Test can bus with a multimeterTest wiring Test can busChamberplus system level studio: usb diy We would like to show you a description here but the site won’t allow us. In this Oct 20, 2019 · Here are different test you can perform using only a multimeter. After the ignition key is turned on, the power relay will provide power to the ECU. Turn the dial (rotary switch) to Diode Test mode. The meter will emit an audible tone when continuity is detected between two points. 6 volts. Look for the screws that hold the lid on the phone line box. The step-by-step guide to testing and troubleshooting a 3-way switch will be provided throughout this article. The 12V lines you can easily test with a multimeter. Step 2: Set your multimeter to measure resistance (ohms). • To test the voltage the truck should be in the state of ignition ON, engine OFF, and batteries connected. The voltage in a LIN bus is typically very low, usually between 1V and 20V. 5 ohms. Testing your doorbell wires with a multimeter is an easy process that can help you identify any issues quickly and easily. 5 V down to 1. com/share/65These 5 diagnostic tips will quickly help you identify if you have a CAN Bus networ Feb 23, 2023 · Bus rates depend on the CAN implementation and are affected by the actual length of the network. Check DC Voltage | A- and Earth GND (Set to DC) Common Issues Earth Ground Normal Reading 2. The 1 Mbps data rate is for a network length of 40 meters (m) or less. Dec 13, 2023 · Step 2: Plug those probes into your outlet (carefully!), and watch as the multimeter works its magic, giving you the lowdown on your outlet’s electrical health. If a fault is detected in the wiring, the affected section may need to be repaired or replaced. Usually, these will be color-coded and labeled L1, L2, and L3. This quick tutorial will teach Jan 29, 2024 · Bus test layer physical connection diagram serial decoding perform connect connector diagnostic picoauto typical picoscopeDiagnosis instruction resistor termination ohms Epcb picoscope ctb diagnostics breakoutBus test resistance check multimeter. Feb 4, 2024 · 1. Nov 14, 2013 · This video gives you step by step instructions on how to use a volt ohm meter to test the electrical wiring on irrigation controllers. 5. CAN Bus Training Now Live for $10!https://www. Nov 26, 2023 · The wiring diagram of the 6-bus test system. A- Greater than 3 VDC: A NetSensor is shorted on the A Sep 19, 2022 · How To Use A Multimeter To Test Voltage Of Live WiresToday you will see how to use a multimeter to test voltage of live wires. The CAN has 2 wires only, a twisted pair these carry the CAN H for high, and the CAN L for low, should a fault occur in one of these lines Jan 19, 2024 · Welcome to the ultimate guide on CAN BUS Diagnosis! In this video, we dive deep into the intricacies of troubleshooting faults in the CAN BUS system. You can use a resistance test to check the Tip 1: Perform a Function Test. 5 V up to 3. They should be infi­ni­te high becau­se no wire is. Jan 4, 2020 · The first step when testing a trailer wiring harness with a multimeter is to make sure that all of the connections are secure. After completing this training, individuals will be better prepared to: The fundamentals of CANbus and focus on the physical layer. – If the multimeter shows a resistance reading close to zero, it confirms the presence of a short circuit. See part 2, checking lighting system with an ohm meter. 0VDC. 99% of the time you come across DC Voltage, it will be below 30 volts DC. Turn the meter on if it has a separate power switch. Mar 3, 2024 · Step #5: Probe the Circuit. May 30, 2023 · Step 2: Set Your Multimeter. Just like with the previous types, a beeping multimeter is a first class sign that the fuse is fine. The multimeter should display a voltage reading close to zero if the breaker is Apr 17, 2024 · 1. Start by inspecting the trailer wiring connections visually, looking for any rust, corrosion, missing parts, or loose connections. The multimeter will display the voltage in volts. To ensu­re cor­rect bus cabling, it is recom­men­ded to per­form the wiring test at the begin­ning of any plant Nov 5, 2022 · In order to test can bus wiring with a multimeter, you will need to first connect the positive lead of the multimeter to the can high wire, and the negative lead of the multimeter to the can low wire. Place the other probe on the neutral bus bar, where the white neutral wires are connected. Apr 29, 2022 · Damage from lightning or transients typically causes a short to ground on one or both CAN lines. Make sure the black probe is connected to the ground point and the red probe to the metal frame or casing of the equipment you are testing. automatetraining. You do this Tony Warwick shows how to use a multimeter to check if there is a break in a wire. Connect the probes and set the dial to test for continuity. com and start your f caution. If you reverse the probes, you won't get an accurate test result. It should have one 120 ohm resistor parallel in each end, so the ohm meter should then show 60 ohms. When multimeter measures resistance in ohms, it can not measure continuity because resistance and continuity are opposites. If your termination is correct, you should read Apr 1, 2020 · Additional troubleshooting tips and resources here: https://support. Ensure safety: Before starting any testing, make sure the vehicle is in a safe state, the engine is off, and the ignition is turned off. Ensure the multimeter is properly calibrated and the probes are connected securely. Once the wires have been identified, they need to be connected to the multimeter. Feb 4, 2014 · Using a multi meter to troubleshoot and check the voltages and grounds on a trailer light connector. Jul 22, 2021 · CAN and CAN FD networks require 120 ohm termination resistors at each end of a CAN bus network. Turn off the guitar and unplug it from the amplifier. Check your thermostat's resistance after disconnecting it from your HVAC system, if applicable. However, if your relay fails, then the starter motor will not receive the necessary power to start the engine. com/share/65This CAN Bus resistance check is very easy and simple WHEN DONE CORRECTLY. For example, using development board and a HOW TO TEST CAN BUS WITH A MULTIMETER [CAN Bus Voltage Check | CAN High and CAN Low Wiring Check] comments sorted by Best Top New Controversial Q&A Add a Comment Top posts of June 16, 2020 Top posts of June 2020 Top posts of 2020 "How a communication bus is wired determines how you diagnose it!" In the second part of this three part series, we dive deeper into CAN Bus wiring and how t Connect: The easiest way to access the CAN bus to via the vehicle service OBD port inside the vehicle. Touch each probe on one of the fuse’s leads or contacts. Next, leave the single probe into the ground hole, and you place the other probe to the negative hole. Measure voltage on any of disconnected plugs between CAN HI and GROUND. Turn the dial on the multimeter so it points to the continuity setting, which looks like 5 curved vertical lines. caution. Can Bus Training Now Live From $10! Web set up and test the multimeter. 4. The video shows how to To troubleshoot CAN bus wiring issues, it is important to use a multimeter or an oscilloscope to check the resistance and voltage levels on the bus. Web web how to test can bus with a multimeter [can. In Order To Test Can Bus Wiring With A. It is essentially a low-speed, single-wire serial data bus (a sub-bus of the faster, more complex CAN Bus) used to control low-speed non-safety-critical housekeeping functions on the vehicle, especially windows, mirrors, locks, HVAC units, and electric seats. Example: Test an outlet receptacle with a multimeter: Let’s assume the outlet is secured in its place and all the wiring is connected correctly. My experience with malfunctioning EOBD ports is mostly bad contact. If yo Nov 14, 2022 · A great tool to use for doorbell testing is a multimeter, which allows you to measure the electrical current and resistance of the wires. Touch the metal parts of your terminals together to make sure it works. Locate the fuse box under the hood. 4V 1. Plug the red probe into the slot marked with a plus sign. 2. Step 5: Testing the Signal Wire. How To Test Can Bus With A Multimeter. Insert one probe to the ground wire and the other probe to the socket’s positive hole. 2 days ago · 3. NOTE: Battery condition is important and should be in the range of 12. Web how to diagnose can bus with a multimeter. If the reading is close to 120 volts, the fixture is working properly. The CAN Bus Troubleshooting PDF sheet is packed with the most important must have information for engineers and technicians to troubleshoot and solve issues with CAN bus in their application, no matter if automotive or industrial. Jun 18, 2023 · Set the selector switch to the ohm symbol (Ω). 0 - 2. This situation is typically seen on the bench with a very small length of wire (1-3ft) in low noise environments. Jul 21, 2017 · Next, place the black probe on the negative end of the battery and the red probe on the positive end. Make sure any CAN nodes e. Connect the yellow lead to Channel A of the scope and to pin 6, then the black pin to pin 4 (Chassis GND). First, trace the root of the wire for how it is connected to the power board. . Unscrew and remove the screws, then take off the plate. 8. Disconnect all devices except for the device being tested, then power the device on. Battery short car find electrical draw test parasitic dmm vehicle multimeter motor circuit voltage meter lead dead cars starter hoursWiring termination instruction and Finding can bus faults with multimeter. 4 days ago · Step 1 – Setup area to test fuses. Jun 23, 2018 · I just wanted to share a quick tip for anyone dealing with a CAN BUS problem. Jun 16, 2023 · To test for an open circuit, the multimeter must be set to the appropriate testing mode and used to measure the resistance of the circuit. Connect the test leads to the diode. After finding that component you will be checking for a short circuit, connect your multimeter’s red and black probes to the circuit. Use a fuse puller to remove the fuses, starting with the ones with the smallest amp ratings and working toward the ones with the highest amp ratings. Here's how you can test the CAN bus with a multimeter: Step 1: Disconnect the CAN bus connector from the electronic device you want to test. Jul 3, 2023 · Method 2: Resistance Test – Set your multimeter to the resistance test mode. Web how to test can bus with a multimeter [can bus voltage check | can high and can low wiring check]. Every 10 seconds your meter should send several 8 bit serial data bytes at up to 2400 Bd, which should show on the multimeter as a momentary DC voltage of ~1. These known good waveforms have the following characteristics: The CAN-L and CAN-H waveforms mirror each other about 2. Apr 22, 2014 · The CAN is a high speed data bus for communication for the electrical components in the engine and body, it is also used for fault finding as any faults are logged and stored to make fault finding easier. When servicing a CAN bus line, ground yourself by touching a metal object such as an unpainted water pipe. The readings should fluctuate between 0 and 5 volts or show a frequency, depending on the vehicle’s specifications. When the circuit is open, no electricity will travel between the two leads and the multimeter will display a reading of “OL” or Apr 7, 2024 · Step 05: Resistance Testing of thermostat wires with multimeter. However, given the robust nature of CAN it often “will work” with only one termination. Step#3- Read the Voltage: The voltage reading will be displayed on the screen of your multimeter. Checking CAN Voltage. Get better training, visit http://www. This mode allows you to check if a wire is continuous or broken. Last, in the positive hole, you leave a single probe. Jan 2, 2020 · The first step to using a multimeter to check phase rotation is to identify the three wires that make up the circuit. Be sure to check that the clips are firmly attached and not loose, otherwise you may receive inaccurate readings. To test the continuity setting’s calibration, touch the 2 terminals together and hold them in place. To effectively diagnose CAN Bus issues, you need to comprehend the network topology specific to your vehicle. This gives you access to the phone lines and a jack where the external phone line connects to your internal line. Step 3: Place the multimeter's leads on the two pins of the Apr 23, 2014 · I haven’t checked, but you should be able to use an ohm-meter to check that you have a complete CAN bus. The short­ing plug con­nects all wires of the bus at the end of the cable. If you did not dis­con­nect some nodes, the deter­mi­ned length could vary. What is covered in this video: 00:42 CAN-BUS Basic 01:16 CAN-BUS total resistance test 03:30 CAN-BUS resistance check CAN Bus Training Now Live for $10! https://www. Multimeter settings may vary, so make sure to look up your multimeter’s user manual for more information. Record the measurement displayed. Select the continuity testing mode if it has a dial or a menu. Step 3: If the reading goes above 120 volts, it’s a red flag indicating that the outlet isn’t safe and needs fixing or replacing. Place the cloth/paper towel on a flat surface such as a table. The CAN bus B network system is connected like this: Set your multimeter to a 200V setting in AC voltage. This will test the resistance in the wire if any, the idea is to have 0. If the power source is left on, it could cause damage to both the multimeter and the circuit being tested. Next, let's move on to current. This CAN Bus diagnostics test is very easy and simple WHEN DONE CORRECTLY. 6V and 12. Sep 7, 2023 · 2. A digital multimeter should be used. Connect the red lead to Channel B of the scope and to pin 14. Make sure that the harness is plugged in correctly and the connections are secure. To test, disconnect the device (under test) from the CAN bus. Start by checking that the power is on and the electricity is working. The first step in testing for an open circuit is to turn off any power source connected to the circuit. com/share/65How to diagnose CAN Bus with a multimeter. Running through the above can help you find the area of emphasis needed to repair CAN bus system issues. If the reading is a flat 0, that’s fine too. Now turn the connector over and count from the end that you referenced. Course Objectives – What you’ll learn. Can-bus tester 2-標高電子 How to test can bus wiring with multimeterIn our garage: installing a new wiring harness. After this, turn the multimeter on and take the reading. Connect both multimeter probes to the thermostat's two terminals. A proper diagnostic strategy includes the use of a good bi-directional scan tool. Start the engine and observe the multimeter’s readings. Aug 2, 2022 · This video shows you how to test the CAN-BUS with a multimeter. Set the multimeter to Ohms or Resistance. -. In the video I will explain how I used this technique to solve a problem on a 2 This sub is dedicated to teaching the fundamentals of automotive systems and programs. Test for voltage. Then, check for power at the port by checking for voltage. Apr 10, 2023 · Step 3: Connect the Multimeter Leads To The Wires. Test the voltage at the lighting outlet box. Aug 4, 2022 · The first step is to check the other components of the circuit, such as the light bulb and the breaker. Use a Digital Multimeter to diagnose and repair issues with CAN wiring. To measure voltage, connect the probes of your multimeter to the points you want to measure and set the multimeter to the correct voltage range. 5 V and have a 1 V peak to peak amplitude. 7 V (50% of 3. The very first step involves setting up the area for testing correctly. Before testing the wire, make sure Nov 14, 2023 · Set the multimeter to "Ohms" or resistance setting to check grounding. Then, you can test the hot wires with fluke multimeters to identify the culprit wires while taking the voltage test. Feb 12, 2015 · Step 1: Pull codes and perform a vehicle health check. Mar 28, 2024 · Check your manual to locate the fuel pump relay. mechanicmindset. Once the leads are connected, you will need to set the multimeter to the resistance setting and then measure the resistance between the can high Mar 9, 2024 · Busbar wiringHow to test can bus with a multimeter [can bus resistance check. Mar 4, 2024 · Step 6: Connect the Multimeter. It may share a space on the dial with another function. Now, take your voltmeter and switch it to ohms. If you have the advanced gear like function generators and spectrum analyzers you can also test the maximum speed the cable in question can carry (e. Feb 1, 2024 · This blog post provides a comprehensive guide to testing the CAN bus with a multimeter, empowering you to troubleshoot and maintain your vehicle’s electrical systems effectively. Select the resistance (ohms) mode on your multimeter, preferably a low range like 200 ohms. g. The longer the network, the lower the maximum data rate it can sustain. This setting allows you to measure the electrical current running through the headlight wiring. At the same location, measure voltage between CAN LOW and GROUND. Then, connect one lead of the multimeter to one terminal of the EGR valve and the other lead to Sep 23, 2016 · Before testing the wire, make sure your multimeter is working. Check the Voltage of the EGR Valve: The first step in testing an EGR valve with a multimeter is to check the voltage at the valve. com/hc/en-us/articles/360038856494-CAN-BUS-Properties-Troubleshooting-G Step 3. Measure the Network’s Impedance. For the metal tip of the black probe, you should connect it to the ground or chassis of the electrical circuit. Make sure power is off to the CAN device under test. Now, you need to test the ground connection. First, connect the positive lead of the multimeter to the positive terminal of the battery, and the negative lead of the multimeter to the negative terminal of the battery. Apr 7, 2024 · Step#2- Connect the Red Lead: Test the headlight wiring by touching the red (positive) lead of your multimeter. CAN bus can be tested with CAN diagnostic software or an oscilloscope. Here are the steps on how to test the guitar wiring with a multimeter: 1. The low and high voltages and transitions between them are You can easily google electric wiring diagrams and connector diagrams for the EOBD port. When there is little resistance, there will be a great deal of continuity, and vice versa. Just touch the tip of the multimeter on it. Before you test the fuse, put the positive and negative leads together and listen for the meter to beep to ensure it’s working properly. Mar 20, 2022 · When starting your vehicle, the relay will close the circuit and energize the starter motor, which then turns your engine over and gets it running. Make sure that the test leads are properly connected to the multimeter, then connect the red lead to one end of the circuit and the black lead to the other end. The resulting voltage should be between 2. Web how to test car wiring with multimeter. Using a multimeter set to measure resistance, check the impedance of the CAN Bus network without the termination resistors. Start by setting up your multimeter. Have a friend "crank" the engine. If your multimeter is set to Ohms mode, you should see a reading of around 1. How to test CAN Bus with a multimeter. Low resistance readings (close to zero ohms) indicate good grounding, while high or infinite readings suggest a problem. You should connect it to the wire that supplies power to the headlights. The loop impe­dance and the cable length are deter­mi­ned. Set the multimeter to measure ac or dc voltage as required. Apr 7, 2024 · Step 2: Set up the multimeter. It’s important to make sure the connections are secure and insulated. Set your multimeter to “Volts DC” mode. Take a look at the reading on the screen. Learn how to stretched or crushed wire. Feb 4, 2024 · Pull out the fuses one at a time while watching the multimeter reading. If the multimeter shows a positive voltage, then the wire that the Oct 14, 2021 · Set up the multimeter. 3 V) on average. Oct 12, 2023 · How to test connections and wiring using multi meter. Aug 5, 2023 · It can be likened to the pressure of water in a pipe. Ensure everything is solidly connected. Make sure to connect the black test probe to the wire labeled “negative” or “ground” and the red test probe to the wire that is being tested. There is a +12V, a -12V, and some different CAN bus lines. B+ Greater than 3 VDC: A NetSensor is shorted on the B+ side. Apr 9, 2020 · CAN Bus Diagnostics training now live for $10! https://www. You can perform a voltage test to see if the Can bus is active or shorted. 5 and 3. Communication is differential using the two wires in the twisted pair, designated CANH and CANL; the CAN CAN Bus Training Now Live for $10! https://www. Since we have the multimeter set to a high 200 volts, it shows "1. To test for voltage, you will need to connect the multimeter probes to the two points in the circuit where you want to measure the voltage. This will provide power to the car's electrical system and, thus, to the spark plug you're holding (assuming your ignition coil is working). The slot marked as -COM is meant for the black probe. Jan 23, 2021 · Next, connect the multimeter’s test probes to the wires in question. Reverse the test leads. Otherwise, the fuse has blown and needs replacing. To do this, disconnect the electrical connector from the EGR valve and set your multimeter to measure DC voltage. Locate the solenoid: The starter solenoid is typically mounted on the starter motor or on the fender well. In this video we install various faults Feb 26, 2021 · Testing CANBUS , OBD2 connector Diagnostics with multimeter CAN BUStest the voltages and resistance to check the OBD2 canbus systems are functioning properly Mea­su­re­ment 2: line-break test. 7. Dec 29, 2023 · In this comprehensive tutorial, I'll guide you through the essential steps of testing fuses with a multimeter using the resistance test method. 2 days ago · Plug the probes into the ports on the multimeter. Get a friend or assistant to turn the key in the vehicle's ignition. If not, the wires are reversed. Jan 19, 2024 · To test a starter solenoid with a multimeter, you can follow these steps: 1. 5 V and the CAN-H waveform switches from 2. Sep 15, 2016 · This is a short promo from AutoMate's training video covering LIN BUS Diagnostics. Bus low high resistance ohms between should speed tutorial line read Multimeter से wiring कैसे check करेंBus test resistance check multimeter. Look for a pair of open ports on the bottom left and right corners of the multimeter. To test the signal wire, touch the positive probe of the multimeter to the wire’s terminal and the negative probe to a good ground. 5 V. Take the red test lead from your multimeter and connect it to the positive terminal of the landscape light. Aug 29, 2021 · Can I use a multimeter to measure the voltage or resistance between GND and TX (DATA_OUT) on my meter, and expect a change every ~10 seconds? Yes. This can help identify any breaks or short circuits in the wiring. 6" on the screen, meaning 1. The result should be Mega ohms or open. Number 4: Continuity. By this point you would have safely removed the fuses from which ever circuit it was connected. If the number on the multimeter is less than 1, then your multimeter is functioning correctly. Turn the meter on and set it to measure continuity. In this case we will be using a Ford IDS Scan Tool (While this is the factory scan tool, techs can also use aftermarket scan tools such as the Delphi Scan Tool or Snap-on Solus). com/share/65Here we look at how to test CAN Bus network for possible faults. Waveform notes. – Connect one probe to a known good ground and the other probe to the wire you suspect of having a short circuit. When measuring resistance value or voltage in CAN bus lines, use a digital multimeter. 10BASE-T, 100BASE-TX, 1000BASE-T, 10GBASE-T or 40GBASE-T, at speeds 10, 100Mbps, 1, 10 and 40Gbps) Number 3: DC Voltage. Finally, check the ground connection to the computer by using the multimeter continuity function. To test the circuit breaker, place one probe of the multimeter on the screw terminal of the breaker, where the load wire (usually black or red) connects. The CAN-L waveform switches from 2. rf of su kk tr ti af rj ef lm