you dont you need an ammeter for that
Purchase, borrow, or have someone with a volt meter or multimeter check it for you. If you don't know what a volt meter or multi meter is, have an electrician check it for you.
Use a volt meter Plug a 120 volt accessory into it
test light or volt meter
Normally red. Check the wires with a volt meter to be sure.
Remove the battery and check it with a volt meter.
With a digital volt meter.
Divide the power rating (in watts) by the voltage (in volts). So if you use a 100 watt light bulb in a typical 110 volt lamp then it will draw 100/110 = .91 amps of current. Or plug a 1500 watt electric heater into a 110 volt wall socket and it will draw 1500/110 = 13.6 amps of current.
The answer is 12 volts, unless the ohms meter says different,check first before you assume.
put a volt meter on the battery and check reading and see if it matches the metere in the car if over 15.0 volts, alternator is likely over charging
To check a cam sensor you can either use a scanner which plugs into the vehicle communication port or use a volt meter and check if the sensor produces a pulse like reading on the meter.
Check for broken wires. You can check for this using a simple cheap volt/ohm meter.
The answer is 12 volts, unless the ohms meter says different,check first before you assume.