Lincoln Mark Lt Brake Lamp Failure Switch
How to Diagnose Lincoln Mark LT Brake Lamp Failure Switch
Fixing the problem of your Lincoln Mark LT brake lamp failure switch seems simple and straightforward. If the brake lights don't come on when the brakes are applied, replace the switch. The question is, do you know how to diagnose the problem, and are you sure it is really the switch? The guide below will help you find the problem in a particular situation and identify what actions you need to take. Take note that the switch is the one that turns the brake lights on when you depress the brake pedal, hence you'll know you have a bad switch if any of these two happens:
Brake lights stay on
There are a few things that account for brake lights that don't go off. The most common is a bad brake lamp failure switch. Over time, the switch wears out and the contacts fail to disengage. When it does, the switch continues to supply power to the brake lights even when the brakes are not applied. To test if the switch still works, remove the switch and test if the plunger and switch are making contact. If the lights work, the switch is bad and needs to be replaced. Also check if the pedal and the plunger are properly aligned. Sometimes, one of these components may slip out of position, causing the switch to stay in the on position or not to return to full off position. If this is the case, you only need to realign them back in place.
Brake lights don't turn on
Other factors besides the brake light switch could be blamed why your brake lights won't turn on. Check if the light wiring is good, the bulbs are not busted, and the fuse is not burnt. Once you know that all are working properly, check the switch. Make sure that it is making a full contact with the plunger. If it does and the lights are still not working, remove the switch and test if there is a full circuit (like what you do if the brake lights stay on). If the brake lights turn on, the switch must be replaced.