Home Button

Prices Button

Services Offered Button

About Us Button

Contact Us Button

Where We Are Button

Domestic Electrical Button

Commercial Electrical Button

Search This Site Button

Site Map Button

Light Switch Problems

This web page describes the purpose of a light switch then gives information about fixing light switch problems.

 

This web page has the following sections:

  • Purpose of a light switch.
  • General debug information.
  • What can go wrong with a light switch.
  • Symptoms of a broken light switch with possible causes.
  • Light switch fixes.

Purpose Of Light Switch

The purpose of a light switch is to connect electrical power to, and disconnect electrical power from, a light:

  • Connect electrical power to a light (turn the light switch on).
  • Disconnect electrical power from a light (turn the light switch off).

Light Switch Closed (On)

The light switch below is ‘closed’ (on).

Light switch schematic diagram - switch closed

 

Electrical power can flow through the light switch to the light.

 

Electrical power passes through the light switch to the light and then to earth.

 

The light ‘lights’.

 

 

The light switch below is ‘open’ (off).

Light switch schematic diagram - switch open

 

Electrical power cannot flow through the light switch to the light.

 

Electrical power is ‘available’ at the light switch but does not pass through the light switch.

The light does not ‘light’.

 

Whatever a light switch look likes its purpose is to allow, or stop, electrical power flow to a light.

 

General Debug Information

Remove power from the light switch circuit before trying to fix a light switch.

 

You get what you pay for – cheap light switches will be poor quality.

 

Connect the electrical power input wire to the switch output to bypass the switch – if the light works the switch is at fault.

 

You cannot repair most light switches – replace the switch.

 

Take note, or a photo, of the switch wiring to help putting the switch back together.

 

What Can Go Wrong With A Light Switch

  • Loose wiring in switch.
  • Switch mechanism broken.
  • Damaged wiring.
  • Bare wires touching the switch housing.

Symptoms Of A Broken Light Switch With Possible Causes

Remove power from the light switch circuit before trying to fix a light switch.

  • Light switch does not work:
    • Loose wiring in switch.
    • Broken switch.
    • Poor connection to light switch terminals.
    • Bare wires touching the switch housing.
  • Light switch ‘buzzing’ or discoloured:
    • Loose wiring in switch.
    • Internal arcing.
    • Bare wires touching the switch housing.
  • Switch hot:
    • Loose wiring in switch.
    • Bare wires touching the switch housing.
  • Lights flickering:
    • Loose wiring in switch.
    • Poor connection to light switch terminals.
    • Bare wires touching the switch housing.

Light Switch Fixes

Remove power from the light switch circuit before attempting to fix a light switch.

The following actions will fix most light switch problems:

  • Remove the wiring from the light switch connectors, snip off the bare wire, strip off the insulation then reconnect the wiring.
  • Clean all metal electrical connections.
  • Replace the switch.

 

Judge Electrical Limited
15 Mulberry Court, Huntington, York, YO32 9TU
Telephone 01904 764845 (Landline), 07919 033113 Mobile)
Email info@judgeelectrical.co.uk
VAT No. 852917405. Company Number 6359328