Why when you apply the brakes with headlights on would brake lights go out a 2001 Jeep Grand Cherokee?

The brake lights going out when the headlights are on and the brakes are applied in a 2001 Jeep Grand Cherokee is likely due to a faulty brake light switch. The brake light switch is a small electrical switch that is located near the brake pedal. When the brake pedal is depressed, the switch is activated and sends a signal to the brake lights, causing them to illuminate. If the brake light switch is faulty, it may not be able to send a signal to the brake lights, causing them to go out when the brakes are applied.

To fix the problem, you will need to replace the faulty brake light switch. To do this, you will need to:

1. Disconnect the negative terminal of the battery.

2. Locate the brake light switch. It is usually located near the brake pedal.

3. Disconnect the electrical connector from the brake light switch.

4. Remove the brake light switch from the vehicle.

5. Install the new brake light switch.

6. Reconnect the electrical connector to the brake light switch.

7. Connect the negative terminal of the battery.

8. Test the brake lights to make sure that they are working properly.