Modern cars and vehicles are equipped with lots of electric circuitry due to addition of more automated systems with time. Now with 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,s electric systems become more complex and challenging. Luckily we have some special automative 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 required a detail guide with steps to follow. Although you may use automotive multimeters also for general purpose home or office use, but 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 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 connector near headlights. Now task is to check ground wire and power flow. Connect one of multimeter,s probe to ground wire and other to 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 voltage stabilizer. Its main purpose is to give a stable voltage supply to audio system, lights and other equipments. So it,s better to test stabilizer first before testing malfunctioning element in car to make sure about power supply. Some times you may receive false errors or alarms on car screen, in that case check stabilizer output first before testing instruments one by one.
To check voltage stabiizer 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 significant lower reading then it may indicate a possible fault within satabilizer.
How to test Fuel Injector through Multimeter
Fuel injector is a device operated by engine control unit to provide required fuel to engine. Fuel injector recieves 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 peform this test to assure safety matters. One companion will test injector while other ignite the car,s engine. First of all remove fuel pump fuse so it may not powered during 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 ground or any other nearest metal part. Now repeat it with other point of fuel injector, one of the point should give 12v or more. If you do not get 12v then there,s must be problem in 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 setting meter range to rpm whether 2 or 4 stroke. After that insert inductive probe into right socket. This test actually needs two person, one has to start engine and adjust throttle while other will check readings on multimeter.
Once engine has been started, put inductive probe to ingnition 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 fuse of affected area. Suppose it,s a radiator fan that stop working suddenly and you have no idea what to do now. After indentifying fuse next step is to set meter knob to continuity function. After removing fuse now connect multimeter probes to fuse socket terminals, if multimeter give beep sound or showing resistance that means circuit is fine. Similarly you can check continuity of fuse.
Another more precised way is to disconnect battery positive, connect multimeter red probe to load side of 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 volatge at anyone of its two terminals.