A Leviton switch/outlet combination device (such as the Leviton 5243-W or 5245-W) replaces a standard duplex receptacle, allowing a single-gang box to control an overhead light while simultaneously providing a receptacle. The exact wiring path depends entirely on whether the internal brass break-off tab remains intact (switch controls the receptacle) or is removed (switch controls a separate light, receptacle is always hot).

⚠️ MAINS VOLTAGE WARNING: This procedure involves 120V AC line voltage. De-energize the circuit at the breaker panel, apply a lockout/tagout device if in a shared environment, and verify the circuit is dead with a non-contact voltage tester and a multimeter before touching any conductors. Local AHJ (Authority Having Jurisdiction) codes may require a licensed electrician for this work.

Physical Terminal Mapping and Spec Sheet

Before stripping any wire, you must understand the physical layout of the device. The most common point of failure in combo device installation is misidentifying the switched-leg terminal from the line-hot terminal. On the Leviton 5245-W (15A, 125V), the terminals are color-coded and physically separated to enforce correct polarity.

Terminal / Pin Color & Location Function Wire Color (US NEC) Torque Spec
Line Hot Brass (Top Right) Incoming unswitched 120V AC power Black (or Red) 14 in-lbs
Switched Hot Black (Bottom Right) Outgoing power to the light fixture load Black (or re-identified White) 14 in-lbs
Neutral Silver (Left Side) Return path for both outlet and light White or Gray 14 in-lbs
Ground Green (Bottom Left) Equipment grounding conductor (EGC) Bare Copper or Green 14 in-lbs
Break-off Fin Brass (Between Hot Terminals) Isolates Line Hot from Switched Hot when snapped N/A N/A
Pro-Tip: Wire Strip Gauge. Use the built-in strip gauge molded into the back of the Leviton yoke. For 14 AWG solid copper, strip exactly 5/8" (16mm) of insulation. Over-stripping exposes bare copper outside the terminal saddle, creating a short-circuit hazard; under-stripping traps insulation under the screw, causing a high-resistance connection that will melt under load.

Node-by-Node Wiring Trace: Source to Load

The following trace maps the most common and complex configuration: Power at the switch box, switch controls a separate overhead light, and the receptacle remains always hot. This requires a Leviton 5245-W (or breaking the tab on a 5243-W) and assumes a 15A circuit using 14/2 NM-B cable.

  1. Source Entry (Line): The 14/2 NM-B cable from the breaker panel enters the single-gang box. The bare copper ground wire is routed to the back of a metal box (if applicable) via a green grounding screw, or wire-nutted to the load ground if using a non-metallic box.
  2. Ground Path Bonding: A 6-inch 14 AWG bare copper pigtail is connected to the incoming ground and the load ground using a twist-on wire connector. The other end of this pigtail is terminated under the Green ground screw on the Leviton device. This bonds the device yoke to the equipment grounding conductor.
  3. Neutral Path: The incoming white neutral wire and the outgoing white neutral wire (heading to the light fixture) are spliced together with a wire nut. A 6-inch 14 AWG white pigtail is added to this splice and terminated under the Silver neutral screw on the left side of the device. Polarity check: The silver screw must always receive the grounded (white) conductor.
  4. Isolating the Terminals: Using needle-nose pliers, grip the brass break-off fin located between the top-right and bottom-right screws. Bend it back and forth until it snaps off. This electrically isolates the receptacle's hot bus from the switch's output bus.
  5. Line Hot to Receptacle: The incoming black (hot) wire from the panel is spliced with a 6-inch 14 AWG black pigtail. This pigtail is terminated under the top Brass Line Hot screw. This provides constant 120V to the receptacle.
  6. Line Hot to Switch: A second 6-inch 14 AWG black pigtail is added to the incoming black hot splice. This pigtail is terminated under the Black Switch Line screw (usually located on the bottom or side, depending on the exact Leviton model year). This feeds incoming power into the toggle mechanism.
  7. Switched Load Leg: The black wire from the 14/2 NM-B cable heading up to the overhead light fixture is terminated under the bottom Brass Switched Hot screw. When the toggle is flipped ON, the internal contacts close, sending 120V from the Black screw to this Brass screw, illuminating the light.

Decoding the Diagram Symbols

Leviton instruction sheets use a standardized set of schematic symbols that can confuse DIYers accustomed to residential wiring diagrams. Here is what the specific icons on the Leviton wiring instruction sheets actually mean in practice:

  • Power Source (Circle with a sine wave): Represents the incoming feeder from the breaker panel. In our trace, this is the 14/2 NM-B entering the box.
  • Lighting Load (Circle with an 'X'): Represents the fixture being controlled by the switch. This is the outgoing 14/2 NM-B heading to the ceiling.
  • The "Fin" Icon (Two parallel lines with a dashed gap): This is the most critical symbol. A solid line between the brass terminals means the tab is intact (switch controls the outlet). A broken/dashed line means the tab must be physically removed with pliers (split-circuit configuration).
  • Re-identified Conductor (White wire with black tape): If you are wiring a "switch loop" (where power goes to the light first, and a single 14/2 drops down to the switch), the diagram will show a white wire with black tape. Per NEC Article 200.7(C), a white wire used as an ungrounded (hot) switch leg must be permanently re-identified with black tape or paint at both terminations.

Multimeter Verification and Testing Protocol

Do not energize the breaker and flip the switch until you have verified the physical connections. A miswired combo device can send 120V to the metal chassis of a lamp or create a dead short across the switch contacts.

Phase 1: De-Energized Continuity Testing

Set your multimeter to the Continuity (diode/beep) or lowest Ohms (Ω) setting. Keep the breaker OFF.

  1. Switch Mechanism Check: Place one probe on the Black (Switch Line) screw and the other on the bottom Brass (Switched Hot) screw. With the toggle OFF, the meter must read OL (Over Limit) or infinite resistance. Flip the toggle ON; the meter should drop to < 0.5 Ω and beep. If it reads OL in both positions, the internal switch is defective or your probe contact is poor.
  2. Receptacle Isolation Check: Place one probe on the top Brass (Line Hot) screw and the other on the bottom Brass (Switched Hot) screw. Because you snapped the break-off fin, the meter must read OL regardless of the switch position. If it reads continuity, the fin is not fully broken, and flipping the switch will dead-short the circuit when a lamp is plugged in.
  3. Ground Bond Check: Place one probe on the Green ground screw and the other on the metal mounting yoke. The meter must read < 1.0 Ω, confirming the yoke is bonded to the EGC.

Phase 2: Energized Voltage Testing

Restore power at the breaker. Set your multimeter to AC Voltage (V~), ensuring the leads are in the correct voltage ports (not the current/amps ports).

  1. Receptacle Polarity: Insert the probes into the receptacle slots (short slot to black probe, long slot to red probe). You should read between 114V and 126V (nominal 120V). If you read 0V, the neutral or hot is disconnected. If you read 240V, you have a multi-wire branch circuit (MWBC) error and must shut the breaker off immediately.
  2. Switched Leg Verification: Carefully measure between the bottom Brass (Switched Hot) screw and the Silver (Neutral) screw. With the switch OFF, read 0V. With the switch ON, read 114V-126V.
  3. Ground Reference: Measure between the top Brass (Line Hot) screw and the Green (Ground) screw. You must read nominal 120V. This confirms the grounding path is intact back to the panel's neutral-ground bond, ensuring the breaker will trip in a fault condition.
Troubleshooting a Tripped Breaker: If the breaker trips the instant you energize the circuit, you have likely failed to break the brass tab on a split-circuit configuration, creating a direct short between the line hot and the switched load leg through the light fixture's low-impedance path. De-energize, pull the device, and verify the fin is completely removed.