When we think of burdensome car problems, major issues such as the engine and transmission come to mind. One issue you may not think about because it seems trivial is car door problems. Sure, fixing a key or lock isn't as expensive as most engine work, but the burden is just the same--you can't drive your car. Fortunately, troubleshooting your Mazda's door problem does not require any advanced knowledge. The main causes of a non-functional car door are the keys, keyhole, and door hinge.
Try unlocking the passenger side door or the trunk with the key you are using on the non-functional car door. The problem is likely a broken key if none of the other doors or trunk open. Try a spare key if you have one on hand. The old key may be worn down and no longer fits the shape of the keyhole.
Heat your key over an open flame if the temperature is cold outside. Freezing temperatures can cause the locking mechanism to freeze. A hot key will warm up the keyhole and unfreeze it.
Check to see if there is any debris inside the door's keyhole. This will prevent they key from turning properly. The best way to solve this problem is to spray mechanical lubricant inside the keyhole. This will flush out the debris and lubricate the inner workings.
Unlock the door and pull on the handle. If the door opens an inch or less before freezing up, the locking latch is probably still engaged. Keep the door as open as possible (you may need another person to keep pulling on the door handle) and locate the latch opposite the car door. The latch will be exposed while the door is held open. Use a screwdriver to pull back the latch. The car door should now open but you'll need to take your car to a mechanic to find out why the latch will not disengage.
