How to diagnose motorcycle electrical problems dennis kirk. Today we are going to discuss how and why to perform a voltage drop test. Measure the voltage, turn off the engine, connect the test probes in a second. Chapter 15 troubleshooting 153 will read the voltage drop. Dont overlook relays, switches, wiring, and solenoids in your search, too. Perform voltage drop tests using a digital voltmeter or the external leads of the voltamp tester. Automotive line transient protection circuit alanmartin. Mechanical stress in rotor windings cause inter turn faults short circuits, which can lead to magnetic imbalance in generators and motors. Voltage needs a solid conductive path from battery to component and back again for things to work properly, and when the path gets blocked by a wall of resistance, voltage backs up at that point and thats what this test is looking for, the wall the voltage runs into. In any circuit with a din relay, without looking at a wiring diagram, you know that. Connect the negative test lead to the negative battery terminal.
Due to the way batteries discharge its important that you test the battery after its been sitting for at least an hour to get whats called the resting voltage. Learning how to troubleshoot a motorcycles charging system can be one of the more difficult tasks to fully understand. Diagnosing voltage drops electrical automotive troubleshooting. Basic electronic troubleshooting motorcycle cruiser. If the equipment requires 50 milliamperes, we can use ohms law to calculate.
Once you get the hang of it, i think youll agree that this test method is the path of least resistance to successful, more accurate circuit diagnoses. Performing a voltage drop, or volt drop test is the best way to check wiring. Figure 1 below shows a simple lamp circuit and normal voltage drops. Meter both test points on the millivolt range, and read the voltage drop across the. There are a few tests one can run just on the battery, rather than the. You can voltage drop test the inline fuse by piercing either end and using you voltmeter just as you did across fuse box fuses. Connect the tester leads in parallel with the circuit being tested. The voltage drop test is the most effective way to find bad connections in electrical circuits.
This same test can be performed on the negative side also. You will need a multimeter and the shop manual for your specific motorcycle. Hopefully youve taken the time to read our automotive circuit testing article and are familiar with the basics when it comes to testing automotive electronics. Voltage drop calculations1 nec code questions free online practice test on conductor voltage drop calculations.
A weak ignition spark may also be due to a voltage drop in the ignition circuit e. Big voltage drop at battery with ignition on welcome to. Use a digital voltmeter to find a poor or corroded ground connection. This test will indicate if the shielding is grounded in several places. The voltage output of a device is measured across its terminals and, thus, is called its terminal voltage v. Voltage drop is the quantity of voltage dropped or lost as it passes through a component or resistance in a circuit. Because an ohmmeters battery cant supply the current that normally flows through most circuits, ohmmeter tests usually cant detect restrictions as accurately as a voltage drop test. If all the fuses have been tested and no excessive voltage drop is found, yet there is a drain, suspect the generator voltage regulator circuit, or any component protected by an inline fuse. The method shown above is the simplest and most effective method to test a voltage regulator. Theyre much less complicated than using the tester. You can do this insitu as auto fuses have open test points on them, so no need to remove them or disconnect the battery. To find the node with a faulty transceiver please te st the can transceiver resistance see next page. Terminal 86 supplies power to the relays internal electromagnet. Use caution when inspecting your motorcycle s electrical and charging system.
Unlike car batteries, motorcycle batteries require a bit more maintenance and care. When left uncharged, the leadacid batteries used in motorcycles go through a natural discharging process. Voltage drop solutions automotive electrolysis solutions. If there is any resistance at all between the two places your meter leads are connected to, resistance can be seen as an increase in voltage or pressure on the voltmeter display. The circuit to be tested must be a live, active circuit the very opposite of using an ohmmeter. What about an alternator that puts out its normal charging. In fact, here are the simple motorcycle battery load test instructions from yuasa for using a multimeter. How to do a battery parasitic drain test by checking the. In order to perform a voltage drop test, voltage must be present in a circuit.
Bimmerscans cable drop test uses midtronics conductance technology to send a signal through the circuit to the component under test. View and download indian motorcycle scout service manual online. This is the place where you will find solutions to electrolysis problems with products. Most modern multimeters come with a diode test function. Unless you operate the circuit so current flows through it, you cant measure voltage drop.
Then the voltage will drop because the stator doesnt produce any power anymore there is no varying magnetic field. Easy test for checking a motorcycle starter system positive feed for excessive voltage drops. This causes higher shaft vibrations, resulting in stress and damage to the bearings. What you are looking for is a voltage drop in the millivolts range. If you know how to do it, a voltage drop test should be the next test you perform. To use a multimeter, to check the voltage of the battery before the bike is started the static test. Voltage drop testing voltage drop testing is a vital test when doing any type of electrical work, when done properly voltage drop testing can be used to identify faulty wiring, relayssolenoid and connections.
Were about to take it a step further and explain the benefits of checking voltage drop across component connections. A voltage drop test is a good best practice during your scheduled preventative maintenance or before replacing the battery, starter or alternator, explains clint stohler, director, technical service and training. Ideal voltage drop would be zero or have no drop at all. When you get the time, do some practicing performing voltage drop measurements. Leave the car overnight and test before you start the car in the morning to get a really accurate gauge of the health of your battery. Voltage drop is the amount of voltage lost as it passes through a component or resistance in a circuit. Another way of thinking on this is that the voltage drop is the number of volts that you lost over that connection. A parasitic draw may also be at the root of the bad battery. How to voltage drop test a starter motor circuit justin miller. So heres the whole key to wrap up the voltage drop test. I is positive if current flows away from the positive terminal, as shown in figure 2. However, a higher degree of technical skill is required and the job may be more complex than you anticipate. Does your engine crank slowly or not at all, but when you test the battery and starter both are fine.
To test the ground side of the circuit figure 2, follow the steps below. The forward bias voltage is dependent on the quality of the diodes. Whenever you have current passing through circuit resistance you will have a voltage drop, because. Significant engine trouble can also cause the voltage to drop too far if it is. Voltage drop testing the best way to test wiring youtube. Motorcycle regulator rectifer testing lamberts bikes. This is the place where you will learn to identifytwo different types of automotive electrolysis, and understand their damaging potential this is the place where you will have access to educationand technical assistance based on real handson underthehood testing. The reading you get on the ohmmeter is number of volts you have lost. Does the bike have a parasitic draw thats normal, like a. Record the results below and compare to specifications. How to check a voltage regulator on a motorcycle it. Learn how to fully diagnose your honda motorcycles charging system. How to diagnose car electrical problems by tracing voltage. Ir, where r is the internal resistance and i is the current flowing at the time of the measurement.
One volt drop generally equals a loss of 30 engine cranking rpms. Test c disable ignition so motorcycle will not start. To check for voltage drop simply check at the battery or source of power for a circuit by connecting you meter leads black to dc negative and red to dc positive and check the voltage. How to test a car battery with a multimeter haynes manuals. Measure dc voltage drop from starter housing to negative battery terminal while cranking. Measure dc voltage drop across power cable from positive battery terminal to starter. If the dc voltage is about half of that expected, turn the rectifier off and feel the individual plates of the stack. With the connector unplugged, you can test the stator for both resistance and voltage.
Voltage drop is one of the most common electrical problems showing up. You can test the ground connection side of the starter too. An alternative is to thus diagnose parasitic draw by measuring voltage drop across the fuses. To test for a voltage drop on the ground side of a circuit, figure 2 follow the steps below. How to voltage drop test a starter motor circuit youtube. Indian motorcycle scout service manual pdf download. If dc voltage is present but is much less than expected, the stack will have to be examined. Its a quick and easy test that doesnt require any disassembly and will quickly show you whether or not you have a good connection or a bad one. Lets throw that illusion out, start with a clean slate and learn your motorcycles charging system in the most simple and basic way possible. Voltage drop is simply the loss of energy in a system due to wiring resistance, connections and corrosion. If voltage drop is greater, backtrack through the circuit until the source of the drop is found. How to perform a voltage drop test help with automotive. Other methods exist, such as testing directly at the stator.
Electrical voltage drop varies according to current flow. If you want to duplicate the exact original output voltage, start with a resistor of about 100 ohms and measure. Finite voltage drop results in lowering the dropout headroom of the protected downstream electrical circuitry. This measures the forward bias voltage of a diode i. The voltage drop reduces current carrying capability that displays the same symptoms as a weak alternator or starter and causes premature battery failure. Its the difference between voltage at the source or battery and the voltage at the component. Testing for parasitic draw with a multimeter test meter pro. A multimeterin the diagram above i illustrate how to use your dvom or multimeter in a seemingly strange way. Last week we talked about the standard din numbers used on relays and the incredible utility they represent. Voltage drop or voltage loss testing is a great diagnostic skill you can use to deal with many automotive electrical problems over time, electrical devices wear out and electrical contacts, terminals, and wires may become corroded, loosed, or broken, introducing unwanted electrical resistance that prevents the circuit from working properly. Testing and charging your motorcycle battery on a regular basis is the best way to guarantee a.
Use caution when inspecting your motorcycles electrical and charging system. If you are checking wiring for power, checking for ground, or an open. This indicates resistance in the starter cable or in the connection to the battery or starter. The actual practice of voltage drop testing in part one i covered the theory of voltage drop testing, which is, that unexpectedundesired resistance in a circuit, adding as little as 110th ohm, can cause dim headlights, improper operation of starters, etc. Test the batteries voltage at off to make sure it gives off the right voltage should be over 12 volts with the bike completely off.
431 1251 142 1471 798 106 601 1365 905 549 447 827 1181 1083 1437 195 1076 321 107 582 976 581 1161 605 150 415 1157 285 29 740 1266 178 751 365 176 584 82 634 563