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Brake Light

I drive a 2004 Nissan Xterra. I’m originally from Florida, but have been living in Quebec for just over a year. About 3 weeks ago I started out to run some errands and as I was pulling out of the parking lot the brake light came on. I pulled over and depressed/released the parking brake a couple of times and it stayed on. I proceeded to run my errands and after about 10 - 15 minutes the light went out. The brakes seemed to be working normally the whole time I was driving. When I got home I checked the brake fluid level and it was about halfway between min and max.

Since then the light has come on three more times. Each time the outside temperature is below 15F. It does not come on when the temp is higher. After driving for a short time the light always goes off.

Could there be freezing in the brake lines? Should I have the brake fluid flushed and replaced? I’ve searched my recommended maintenance schedule and this doesn’t appear anywhere in it. The recommended brake fluid for my vehicle is DOT3.

Thanks for any insight.

do you park the vehicle on an incline? i have seen some instances where the brake fluid level would be down in the reservoir and when on an incline the fluid would move away from the sensor and turn on the light then once you level it out the light will go out. just a thought but i would also check to make sure you dont have a leak anywhere. as your pads wear the level in the reservoir drops, i normally dont like to add to the reservoir because if there are no leaks this is a good indicator that your pads are getting worn down and when you go to replace them and push the calipers back out it makes a big mess from the excess fluid that had been added however if your pads are at say 50% wear and the light is coming on for above said reason you may have to add some brake fluid to keep it from happening.

If you never had the brake fluid changed, do it now. While you are in the shop, the mechanic can inspect the brake system to see what is wrong. The brake fluid is oil and will not freeze. Water in the brake lines will freeze. As time progresses, brake fluid will absorb moisture; especially if it overheats. The fluid should be changed ever 4 years or so. Also, check the brake fluid level when it is cold, like this morning. The fluid should not be below the minimum mark when it is cold. You checked it after the fluid warmed up, and it likely swelled some.

@Akula brake fluid should be flushed every 2 years, using a diaphragm brake bleeder and the proper adapter, NOT the 2 man push and hold method.

There are two things that trigger this light, brake fluid level and the parking brake switch. I suspect the parking brake switch froze on you, but as the cabin warmed up, it eventually unfroze.

Thanks for all these comments. I’m going to make an appointment on Monday to have the brake fluid changed and will talk further with the service man to get his ideas about the light. Hopefully the fluid change will take care of it. The pads may very well need replacement, too. For what it’s worth, the car is not parked on an incline, and as far as I know there is no leak … at least no visible evidence of one.

The brake light switch, actualted by the brake pedal, is usually the culprit. I had that happen to my last car; the brake light just stayed on. A new brakelight switch fixed the problem. Somestimes it is just stuck, and can be freed up.

Changing the brake fluid is a good idea, but it may NOT solve the light staying on.

Coming from Florida, it’s not unusual to encounter these cold weather problems, like a frozen parking brake switch.

@Docnick - the OP is referring to the brake warning light, not the stop lights.

Does your brake light normally come on if you have the parking brake engaged and go off when you release it?

@Vhyle Thanks for the correction. The brake warning light coming on can have a number of causes. Low fluid level would be the first to check.