A multimeter is often much less expensive than other complex diagnostic tools and can cost from anywhere from $14 to over $100.
If you’re unsure of which setting is voltage, read the instruction manual that came with the multimeter. A voltage read must never be done with Ohm or Ampere position set as you could damage your device.
Your battery may also have a plastic cap over the battery terminals. Lift the plastic cap to see the positive and negative nodes.
If the multimeter doesn’t read anything, it may mean that the batteries in the meter are dead. It could also mean that the meter isn’t connected properly to your vehicle’s battery.
If your multimeter reads 13. 8, it means that your alternator is properly charging your battery.
You will also need to know how many volts your regulator is supposed to output. Typical voltage regulators for computer equipment will be anywhere from 5-12 volts.
