Three bedrooms on the same circuit. Bedroom1 is closest to the panel, then bedroom2, then bedroom3. The overhead light and receptacles work in bedroom1. The overhead light does not work but all receptacles work in bedroom2. Nothing works in bedroom3. What's the most plausible reason for this fault?

Three bedrooms on the same circuit. Bedroom1 is closest to the panel, then bedroom2, then bedroom3. The overhead light and receptacles work in bedroom1. The overhead light does not work but all receptacles work in bedroom2. Nothing works in bedroom3. What's the most plausible reason for this fault?

• A. Bad breaker
• B. Neutral came apart in bedroom2 switchbox
• C. Bad lamps in rooms 2 and 3
• D. GFCI tripped

Answer: (B)

Open neutral paths are the return route for current. When the neutral conductor opens somewhere in a daisy‑chained circuit, loads downstream lose their return and go dark, while upstream devices can stay powered. Here, the feed runs from the panel to bedroom 1, then to bedroom 2, then to bedroom 3. If the neutral connection opens in the bedroom 2 switch box, the path back to the panel for anything beyond that point is broken. That explains why nothing in bedroom 3 works—the downstream loads have no neutral. It also explains why the overhead light in bedroom 2 doesn’t work—the light needs a complete neutral path, which is interrupted by the open in the switch box. Why bedroom 2 receptacles still work fits with a splice arrangement in that box: their neutral could still be connected via a pigtail to the upstream neutral that bypasses the broken segment, so those outlets have a return path and stay energized, even though the switch loop for the ceiling light shares the broken neutral. This pattern is more plausible than a single bad breaker (which would usually cut power to a larger portion of the circuit), a GFCI that has tripped (which would affect protected outlets in a more predictable way), or multiple bad lamps (which wouldn’t selectively spare the bedroom 2 outlets while bedroom 3 remains dead).

Open neutral paths are the return route for current. When the neutral conductor opens somewhere in a daisy‑chained circuit, loads downstream lose their return and go dark, while upstream devices can stay powered.

Here, the feed runs from the panel to bedroom 1, then to bedroom 2, then to bedroom 3. If the neutral connection opens in the bedroom 2 switch box, the path back to the panel for anything beyond that point is broken. That explains why nothing in bedroom 3 works—the downstream loads have no neutral. It also explains why the overhead light in bedroom 2 doesn’t work—the light needs a complete neutral path, which is interrupted by the open in the switch box.

Why bedroom 2 receptacles still work fits with a splice arrangement in that box: their neutral could still be connected via a pigtail to the upstream neutral that bypasses the broken segment, so those outlets have a return path and stay energized, even though the switch loop for the ceiling light shares the broken neutral.

This pattern is more plausible than a single bad breaker (which would usually cut power to a larger portion of the circuit), a GFCI that has tripped (which would affect protected outlets in a more predictable way), or multiple bad lamps (which wouldn’t selectively spare the bedroom 2 outlets while bedroom 3 remains dead).