Near the back of the engine, on the driver’s side of the car, is a small box or bottle with tubing going in and out. This is the brake master cylinder and it holds a reservoir of brake fluid. In many newer cars, the reservoir is made from translucent or transparent plastic and the level of the fluid can be checked without doing anything except looking.

If you can’t see the fluid level, you will have to remove a cap that may be held on with a retaining spring. The spring can be popped off with a screwdriver. Make sure the area around the cap is clean before opening it. Wipe away any dirt or dust with a paper towel. It is very important not to let any dirt or foreign matter get into the reservoir, because this might interfere with the operation of the brakes.

Remove the cover and the rubber diaphragm that sits beneath it. The brake fluid should be within a half inch of the top in both chambers, or up to the fill line if there is one.

Use ONLY the EXACT type of brake fluid that is specified by the manufacturer of the vehicle. Look in your owner’s manual or contact the dealer. Purchase the smallest amount possible and discard the rest. Once opened, do not store it for use at a later date since it will evaporate and gather moisture from the air, making it unsafe to use.

Carefully, and with cleanliness, replace the rubber diaphragm and cover. It may be necessary to push the diaphragm to its uppermost position with your finger before you can get the cover back on.

Having to add brake fluid once in a while does not indicate a particular problem.

However, finding that you must do so often, indicates a leak somewhere.

Have that situation checked immediately.