When I power anything on at the outlet in my bathroom (which has two outlets and a light switch on the same receptacle) it turns the wall light ON. Should I be worried about faulty wiring?

Answer 1

Answer for Canada, USA and countries running a 60 Hz, 120/240 volt, split supply service.

This sounds like a DIY electrician didn't make the correct re-connections. If "power anything on" means when you plug a device into the receptacle part of the outlet, the wall light comes on, then there is crossed wiring in the wall box.

There should be a minimum of two black and white conductor cables in the box. If the circuit is extended from this box there could be another one or two cables.

This is the point where if you feel conversant with electrical terms and have test equipment you could try and repair the condition or call an electrician.

What has happened is the switch leg for the light switch has been connected across the receptacle. This can happen because the switch leg used a white wire instead of two black wires. So when you plug a device into the receptacle, the device acts as a switch and turns the light on. You might find that the light does not come on completely bright due to the internal resistance in the plugged in device.

At this point an electrician would shut the breaker off feeding the circuit, take the cover plate off the box and remove both the receptacle and the switch. Undo all of the connections and sort out which cable wire does what. This is where the test equipment is needed.

Once the cables are all separated briefly turn the breaker back on and determine what cable brings the supply to the junction box. Mark this cable and turn the power source back off again.

Next determine what cable goes to the wall light. Put the test meter, switched to the ohms scale, across the black and white wires of the cable under test. There should be a reading, unscrew the lamp and the reading should stop. Do this a couple of times to make sure that you have the correct cable.

If there are more cables in the junction box these most likely go to other receptacles that are connected to the same circuit down stream

To reconnect, connect all of the white wires that are in the junction box together plus a short white pigtail for the receptacle's neutral side (silver screw). Connect the white pigtail to the receptacle.

Now take the incoming black "hot" conductor and create two pigtail short wires and the downstream black wire, if there is one, and wire nut all three or four wires together.

One of the black pigtails goes to the receptacle and the other pigtail goes to the top contact on the switch. At this point the receptacle will be across the black and white incoming "hot" cable and the top of the switch will have a "hot" conductor connected to it.

All that is left to do is connect the black wire from the light cable to the bottom of the light switch. To test the circuit before closing everything up, turn on the breaker and flip the light switch to the on position and the wall light should light. If it does, turn the breaker back off again, reinstall the switch and the receptacle, install the cover plate and the project is finished.

As always, if you are in doubt about what to do, the best advice anyone should give you is to call a licensed electrician to advise what work is needed.

Before you do any work yourself, on electrical circuits, equipment or appliances always use a test meter to ensure the circuit is, in fact, de-energized.

IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOB SAFELY AND COMPETENTLY REFER THIS WORK TO QUALIFIED PROFESSIONALS.