Troubleshooting basics procedures

[walters]

What are some troubleshooting procedures

1.) First check the power supply voltage
2.) Check the V+ on IC chips to check if the IC chip is getting power
3.) Check every input and output for each stage of a transistor or IC op amp of the circuit until you find no signal

4.) Can you add any others on the list

A SHORT Will make the circuit have no signal in that stage of the circuit, it will have zero voltage on the PCB board pads in that area of the short, Blocking the path to the next stage of the circuit

An OPEN will make a circuit have no signal in that stage of the circuit, breaking the path to the next stage of the circuit

An OPEN of a component in a circuit can also change the bias or gain of the circuit

If a transistor is shorted internally From either Base, emitter, collector it will change what?
it changes the voltage measurements

If the transistor is open it breaks the path from input to output of that stage so the signal is gone

 

[karthickb3e]

Hi,

from my suggestion...

Current flowing to the circiut also change....

if the current flowing is abnormal(high) there is short in the circuit.....

also current flowing is reduced to normal level ther is open circiut in the connection.......

 

[walters]

Yes a short in a circuit has VERY HIGH current, but how do u measure that in circuit with a DVM? without cutting traces to put a current meter to measure the very high current to know the circuit has a short?

 

[mister_rf]

That's not always true. A shortcircuit in the signal path may not increase the current consumption. Secondly, for most of the circuits we do not have access to the normal power current value, as long there’s a very large margin for that current due to inherent variations in the normal operation of the system (see for example troubleshooting a PC motherboard).