* Low Brake Fluid: This is the most common cause. The brake light is often triggered by a low fluid level sensor in the master cylinder. Check the brake fluid level in the master cylinder reservoir (usually a clear or translucent plastic container). If it's low, you have a leak somewhere in your brake system – a serious issue that needs immediate attention. Do not drive the vehicle until this is addressed.
* Brake Light Switch: This switch is located near the brake pedal and tells the system when the brakes are being applied. A faulty switch can stay "on" even when the pedal is released. This is less likely if the light gets brighter with the e-brake, but still possible if the switch is malfunctioning in a way that the system interprets as constant brake pressure.
* Faulty Brake Light Bulb: While less likely given your description (the light's behaviour with the e-brake), a faulty bulb could potentially cause a slightly unusual behaviour. This is easier to check compared to brake fluid or the switch.
* Problem with the Emergency Brake System: The brighter light with the e-brake engaged suggests the system is correctly indicating the e-brake is on. However, a problem within the e-brake mechanism (like a cable sticking slightly) might be interfering with the normal brake light operation.
What to do:
1. Check the brake fluid level immediately. This is the most important step. If it's low, do not drive the vehicle. A leak means you have compromised braking and could have an accident. Have it towed to a mechanic.
2. Inspect the brake light bulbs. Make sure they are properly seated and functioning.
3. If the brake fluid level is OK, the brake light switch is the next most likely suspect. This is a relatively inexpensive and easy part to replace, but it requires some mechanical skill or professional help.
4. If the problem persists after checking fluid and bulbs, have a qualified mechanic diagnose and repair the issue. Ignoring a consistently illuminated brake light is risky and could lead to more significant problems.
Important Note: Driving with a malfunctioning brake system is extremely dangerous. Do not drive your vehicle until the issue is resolved.
