To properly check voltage in any circuit

You must touch the leads of the multimeter to any two points in the circuit. When you do this, the multimeter displays the voltage that exists between the points

Explanation:

the warning light flashes for a second or two when the engine starts. if it stays on, there's must be something wrong with the coolant. you should never dare to continue driving when the light is on. pull over as soon as possible and shut the engine off.

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