A courtesy light switch is what signals the courtesy light, located in the passenger compartment, to come on and provide the light necessary to see what you’re doing, especially on a dark night. The courtesy light functions by either completing or interrupting the electrical signal that turns on the courtesy light when you open a door.
There can be several switches in a given vehicle, usually determined by the number of entry doors to the passenger compartment. They can also be found on some rear cargo doors on minivans and sport utility vehicles.
Although most of these courtesy light switches are found primarily in the door jamb, they can also be a part of the door latch assembly. For this article, we are going to focus on the courtesy light switches located in the door jamb.
Part 1 of 3: Locate courtesy light switch
Step 1: Open door. Open the door that corresponds to the switch in need of replacement.
Step 2: Locate courtesy light switch. Visually inspect the door jamb for the location of the door jamb switch.
Part 2 of 3: Replace courtesy light switch
- Socket set
Step 1: Remove courtesy light switch bolt. Using a screwdriver or socket and ratchet, remove the screw that holds the courtesy light switch in place.
Set screw to the side in a place that it won’t get lost.
Step 2: Pull courtesy light switch from its recess. Carefully pull the courtesy light switch from the recess in which it sits.
Be careful not to snag the connector or wiring that plugs into the back of the switch.
Step 3: Unplug the electrical connector on the back of the switch. Unplug the electrical connector on the back of the courtesy light switch.
Some connectors can be released by hand while others may require the use of a small screwdriver to gently pry the connector away from the switch.
- Warning: Once the courtesy light switch has been unplugged, do not allow the wiring and/or electrical plug to fall back into the recess. A small piece of tape can be used to tape the wiring or connector to the door jamb, so as to keep it from falling back into the opening.
Step 4: Match up the replacement courtesy light switch with the one being replaced. Visually verify that the replacement courtesy light switch has the same dimensions as the old one.
Also, look to see that the height appears the same and be sure the connector on the replacement switch matches that of the old switch and that the pins are in the same configuration.
Step 5: Plug replacement courtesy light switch into wiring connector. Plug the replacement into the electrical connector.
Part 3 of 3: Verify the function of replacement courtesy light switch
Step 1: Verify function of replacement courtesy light switch. It is easier to verify the function of the replacement courtesy light switch before reinstalling it back into the door jamb.
With all other doors closed, simply depress the plunger on the switch and verify that the courtesy light goes off.
Step 2: Reinstall the courtesy light switch. Reinstall the courtesy light switch back into its recess until it is flush with the panel.
Once it is sitting back in its proper position, reinstall the bolt and tighten it until it is secure.
Step 3: Check for proper fitment. Take a moment to sure the installed height is correct. Gently close the door.
Press firmly on the door while paying attention that there is no abnormal resistance to latching.
- Warning: If there appears to be more resistance to the door latching than normal, this may be a sign that the courtesy light switch is not completely seated or that the wrong switch was acquired. Trying to force the door closed may result in the replacement courtesy light switch being damaged.
The job is complete once the door closes with a normal amount of effort and the operation of the courtesy light switch has been verified. If at any point you feel you could use a hand with replacing your courtesy light switch, contact one of YourMechanic’s certified technicians to come to your home or place of business to perform the replacement.
This article originally appeared on YourMechanic.com as How to Replace a Courtesy Light Switch in Most Cars and was authored by Ty Thompson.