How to Choose a Multi-meter?
When shopping for a Multi-meter, you'll want to decide between an analog and a digital model. Digital Multi-meter s has more functions, and higher input impedance some even connect to smartphone, tablets, and computers. Analog ones are usually limited to the three basic measurements; volts, amps, and ohms.
Before buying a Multi-meter:
1. Does it check DC voltage - Car electrical systems run on DC voltage. The Multi-meter must be able to
read DC voltage to provide accurate data on charge levels. The majority of Multi-meter performs this test, but it's always smart to check.
2. Can it test for continuity - Continuity tests for a break in a circuit or wire that can't be seen visually Multi-meter that beeps while performing a continuity test is a greater help in hard-to-reach areas. The meter should display zero for a bad component, and anything higher than one for a good part.
The average digital Multi-meter, more popular and common than the traditional analog Multi-meter, comes with:
A Display Screen: For viewing measurements.
Buttons: For selecting functions with varying options depending on the model.
Dial or rotary switch: For choosing measurement values (volts, ohms, amps, etc.).
Input jacks: For inserting test leads.
A Multi-meter can be used to test a variety of electrical components in your vehicle, such as:
Car Battery Charge: A low-charged battery may prevent the car from starting.
Checking Battery Terminals: Dirty loose, or corroded battery terminals can contribute to starting problems
A Multi-meter can check the battery connections as well as the battery for a drop in voltage.
Leak Test on Battery Cover: The charge from a battery can slowly leak as deposits build up on the top and terminals. Any voltage that appears when testing this section indicates a drain in the battery charge.
Alternator Function: The alternator produces electricity to charge the car battery while driving. It can be tested just like the battery, but with the car idling instead of turned off.
Sender Units: A Multi-meter can check the fuel tank for continuity by measuring resistance levels at a full, half-full, and empty tank. They should show equal gaps between readings. If they're close together, it indicates shorted out resister tracks.
Ignition Tests: Different components of the ignition system can be measured for accuracy using a Multi-meter . This includes the spark plugs, distributor, and ignition coils.
Car Horn: A Multi-meter can test the fuse in malfunctioning car horn for continuity. An "Out of Limits (OL)" reading indicates a blown fuse.