Ohmmeter junction test logic: If a BJT junction reads low resistance in both directions, it is shorted and the transistor is bad; and if a BJT junction reads high resistance in both directions, the junction is shorted and the transistor is good. Is this statement correct?

Introduction / Context:
Checking a BJT with an ohmmeter (or diode-test function) relies on the diode behavior of the base–emitter and base–collector junctions. Proper interpretation distinguishes shorts, opens, and normal forward/reverse characteristics. The statement in the prompt mixes up the conclusions for high versus low readings and even calls a device “good” when measurements indicate a fault.

Given Data / Assumptions:

• Transistor is removed from circuit or at least isolated to avoid parallel paths.
• Ohmmeter polarity awareness: swapping leads changes which junction is forward biased.
• Silicon BJTs expected forward drop around one diode in forward direction and high resistance in reverse.

Concept / Approach:
A healthy junction behaves like a diode: low resistance (or ~0.6–0.7 V on diode test) in forward direction and high resistance in reverse. A low reading in both directions indicates a shorted junction (faulty). A high reading in both directions indicates an open junction (also faulty). Normal behavior requires asymmetric readings depending on meter polarity. Therefore, declaring the device “good” when a junction reads high both ways is wrong; that indicates an open junction and a bad transistor.

Step-by-Step Solution:

Verification / Alternative check:
Using a multimeter’s diode mode yields ~0.6–0.7 V forward drop for silicon; any reading ~0 V (both ways) indicates a short, while OL both ways indicates open.

Why Other Options Are Wrong:
Device material (silicon vs germanium) alters forward voltage but not the fault logic. In-circuit testing can confuse results but does not reverse the good/bad criteria.

Common Pitfalls:
Testing in-circuit without isolating leads; misinterpreting auto-ranging readings; not reversing meter polarity for both directions.

Final Answer:
Incorrect