The working principle of a voltage stabilizer is very simple, its main function to keep stable the output voltage by increasing or decreasing the voltage level according to the unstable input voltage. ... So drop in input voltage will nothing effect in the output voltage, output voltage remain constant at the normal value.

Do voltage stabilizers really work?

Conclusion, installation of voltage stabilizer and grounding cable does little improvement on the car performance that users are barely notice the differences.

How do I know if my voltage stabilizer is working?

Attach the negative side of the battery to the stabilizer case and the positive side of the battery to the input terminal of the stabilizer. Place one of the meter probes on the stabilizer case and the other on the output terminal if you want to use the multimeter in the correct range.