Modern cars and vehicles are equipped with lots of electric circuitry due to the addition of more automated systems with time. Now with the passage of time automative industry has grown rapidly, electric cars are changing our previous gasoline engine concepts. Even we’ll see flying cars soon with general traffic on roads. So after these advancements now troubleshooting car electric systems become more complex and challenging. Luckily we have some special automotive digital multimeters for this purpose that made life easier.
If you want to know how to use a multimeter on a car, that can,t be covered in a single answer. It will require a detailed guide with steps to follow. Although you may use automotive multimeters also for general purpose home or office use, their special features are designed to sort some critical auto electric problems. Once a car faced some mechanical issues, there is a bright chance that a mechanic has to come across an electric fault. And that could only be checked by a best automotive multimeter.
How to test Car Headlights with Multimeter
Car headlights are primary source of light while driving at night on remote highways. If ever unluckily your car lights stop working or went dim you can do a self test to identify the problem. For this purpose first, you have to turn on multimeter at resistance or continuity range. You’ll find a two wired or four wired wiring with a connector near headlights. Now the task is to check the ground wire and power flow. Connect one of multimeter’s probes to the ground wire and the other to the battery negative terminal. If you read continuity that means ground wire is ok, otherwise, it has to be replaced.
How to check Car Voltage stabilizer with Multimeter
Many modern cars come with this device called a voltage stabilizer. Its main purpose is to give a stable voltage supply to the audio system, lights and other equipment. So it’s better to test stabilizer first before testing the malfunctioning element in the car to make sure about power supply. Sometimes you may receive false errors or alarms on the car screen, in that case, check stabilizer output first before testing instruments one by one.
To check voltage stabilizer turn on multimeter and set its range to 20v dc. Now connect both probes of meter to stabilizer output terminals respectively. The meter should get a reading of plus minus 10 volts. If you get a significantly lower reading then it may indicate a possible fault within the stabilizer.
How to test Fuel Injector through Multimeter
A fuel injector is a device operated by the engine control unit to provide the required fuel to the engine. Fuel injector receives voltage pulse signals for its operation. Car computer controls ground wire reaching to fuel injector by sending on and off signals. So you can check car fuel injector by testing its ground wire. In quality automotive multimeters like FLUKE-88-5 there,s a feature called pulse width measurements through which even milli second readings are covered.
You’ll need an assistant to perform this test to assure safety matters. One companion will test injector while the other ignite the car’s engine. First of all, remove fuel pump fuse so it may not be powered during the test to avoid fuel loss. No de attach fuel injector and tell your friend to turn on car. After that connect one probe of meter to any injector’s terminal and other probe to the ground or any other nearest metal part. Now repeat it with another point of fuel injector, one of the points should give 12v or more. If you do not get 12v then there’s must be a problem in the supply circuit.
How to measure engine rpm with Automative Multimeter
Automotive multimeters are the best option to test rpm of a car engine efficiently. These meters come with a specially built inductive pickup, which helps in measuring rpm accurately. All you have to do is just set meter range to rpm whether 2 or 4 strokes. After that insert inductive probe into right socket. This test actually needs two person, one has to start the engine and adjust the throttle while the other will check readings on multimeter.
Once the engine has been started by car starter, put an inductive probe to ignition high voltage line and see rpm readings on lcd screen.
How to find a short in a Car with a Multimeter
You can find a short circuit in any circuit of your car with help of a multimeter. For this first, you have to identify the fuse of the affected area. Suppose it’s a radiator fan that stops working suddenly and you have no idea what to do now. After identifying the fuse next step is to set meter knob to continuity function. After removing the fuse now connect multimeter probes to fuse socket terminals, if the multimeter gives a beep sound or shows resistance that means the circuit is fine. Similarly, you can check the continuity of fuse.
Another more precise way is to disconnect the battery positive, connect multimeter red probe to load side of the fuse, and negative probe to battery negative terminal. If there’s a short in that particular circuit multimeter will beep.
How to test Car speaker Voltage
Sound system is an essential item in cars, as a primary source of entertainment while driving. With little know how about multimeter usage you can test speakers of your car by yourself. For this take a digital multimeter with dc voltage function and set it to 24v dc. Before this don,t forget to check that multimeter’s probes should be in right sockets. Now connect black or neutral probe of meter to ground or any metal part and red one with one of speaker’s terminal. It should give battery voltage at any one of its two terminals.