How does a multimeter indicate a short circuit?

Question

I need to test the foot pedal (which contains a printed circuit board) for my Minn Kota Power Drive bow mount electric motor. The plug has eight connections, designated A thru H in the reapir manual. The manual says that I should set my multimeter to the X1 scale and the meter should indicate short from A to G, from A to F, from E to F, etc. ( See page 3-4 http://www.konett.com/Minn Kota/Minn Kota Service Information 2004P/RepairManual/Repair Manual.pdf)

What am I looking for on the multimeter? Should the reading be 0? (I assume I should touch one probe to A and the other to G, or one to A and the other to F, etc.)

Answer 1

When you test your circuit, if you find that your meter indicates from 0 to about 5 ohms, you most likely have a short circuit. To simulate what a short circuit looks like on your meter, touch the black and red terminals together, your meter should indicate 0. If you get the same ( or close) result when you test the circuit, it is shorted out.

Answer 2

1) Set the multimeter to reat OHMS, not voltage...

2) Touch the red and black lead of the multimeter and adjust the meter to zero ohms at lowest ohm setting ( 1X)

3) with NO voltage applied to unit (unplugged) follow instructions... a short circuit will be indicated with a Zero reading... or about zero.

4)  And yes, you assume right..one lead to one point, the other lead to the other point

5) make sure the battery in the mulitmeter is new or is at least working...nothing will happen if the battery is dead! IF you cannot "zero" the meter with the leads touching, the battery is dead.

Good Luck, Goldwing

Answer 3

If the meter is reading resistance, make SURE that the device is unplugged before you start.  A short means that two (or more) wires are touching each other where they shouldn't, so there will be little or no resistance (where there should be).  The meter sends a small current from it's battery, and measures how much trouble (resistance) it runs into.

That's the opposite of an open circuit, where you would be looking for a broken wire (lots of resistance).

Answer 4

Shorts in a electrical circuit will blow fuses since a short is the uncontrolled flow of electrons, like when you touch a live wire to ground and see that blue flash that is a short and it will trip a breaker fast. Circuit boards are hard to troubleshoot since to check the components you need to remove them from the board and check then put back on the board. Shorts in a circuit on a meter have no resistance using the Rx1 scale. Remove all wires to this board so you do not get back feed Thur the other circuits. Shorts in circuit boards will in most cases leave a burn mark.