Many different cars with power windows have a master switch. This is usually located on the driver’s side. The master switch is usually able to lower or raise windows. In addition, the master switch is able to disable individual switches. These cars usually have a control circuit that has a reversible motor with a relay and breaker for each individual window. There is also a main relay and a main circuit breaker that controls all of the rest. This type of configuration allows every other window to work even when certain mechanical or electrical problems cause one window to stop working. If you follow a few of these guidelines, you may be able to locate the problem and fix the window that happens to be stuck. The following steps are not all of the ways that you can diagnose a problem. Many of these problems require you to have some knowledge of electricity and a little mechanical knowledge.
Using the Master Control Switch
To start this diagnosis off, you can turn on the ignition. Make sure that you do not start the car’s engine. Once you have done this, operate all of your windows by using the master control switch. If none of the windows works, you will need to check the main breaker for the whole power circuit. If you find that only one window does not work, you will need to check the circuit breaker for the window that does not work. This will be explained later.
Check the Main Breaker
You can check the main circuit relay with a test light. If you can see voltage coming from the main circuit relay, then you have an open wire or a short wire that is feeding power to all of the other switches. If you do not see any voltage coming from the main circuit relay, you will need to use the test light in order to make sure that voltage is actually reaching the relay. If you notice that the voltage is not even reaching the relay, then you have an open wire or a short wire between your main relay and the main breaker.
Check the Circuit Breaker for an Individual Window
Checking the circuit breaker for an individual window that does not work is very easy. You will need to go to the individual controls to do this. If the individual breaker seems to be working fine, then you will need to check the main control lockout switch. If you happen to hear a humming sound when you press your individual switch and the window is not working, then you probably have a bad motor gearbox. You could even have broken teeth. You can get to the motor by taking off the trim panel at the window that does not work. You can check the motor with a test light.
Check the Master Control Lockout Switch
As mentioned in step one, you should turn on the ignition without actually starting the engine. After you have done this, use a multi meter to check the main control lockout switch for continuity. If you notice that there is not any continuity, then you will need to replace the main control lockout switch. Some car models that have problems with the control lockout will have rear windows that have failed.
If this seems to be perfectly fine, then you can try the switch at the window that does not seem to be working. Check for continuity with a voltmeter. If there is no continuity, then you need to replace the switch.
If that seems to be working fine, you will need to check the voltage. You can do this by using a test light. If you notice that the voltage does not seem to be reaching the switch, then you have an open wire or a short wire that is between the incoming wire and the main breaker for the circuit power window.