# Locating ground and other pins on circuit board

I am a beginner attempting to learn how to hack RC cars like is demonstrated in this video.

My problem is I can't spot the ground pin and the other pins related to the wheel drive functions except I randomly test pins with my multimeter.

In an old pair of RC cars, after a long time of trial and error I finally located the ground and one of the pins connected to a wheel.

However, I just wonder if there is a technique for locating ground and other pins in a circuit, please?

I want to learn how to locate the relevant pins so I can hack these cars.

• The "ground" is usually connected to the - terminal of the battery. Then you just check continuity with that point. – Eugene Sh. Mar 8 '18 at 17:59
• data-sheets for the parts involved will also indicate ground... the black wire to the servo is ground... – Jasen Mar 8 '18 at 19:28