1. Identify the Problem:
* Which windows are affected? Is it all windows, just one, or a group (e.g., driver's side only)? This helps isolate the problem to a specific window regulator, switch, or a more general electrical issue.
* What's the symptom? Do the windows not move at all? Do they move slowly? Do they work sometimes but not others? Is there a clicking sound when you press the switch? This points to different potential problems.
* Check the fuses: Locate the power window fuse(s) in your fuse box (usually under the hood or dashboard). Check for blown fuses (a broken wire inside the fuse). Replace any blown fuses with fuses of the correct amperage. If the fuse blows immediately after replacement, you have a short circuit somewhere in the system.
2. Testing and Troubleshooting:
* Window Switches:
* Start with the master switch (driver's side). If none of the windows work, the problem likely lies here or in the wiring leading to it.
* Try each individual window switch. If only one window is affected, the problem is likely in that switch, its wiring, or its regulator.
* Test the switches with a multimeter (if you have one). You can check for continuity (a complete circuit) in the switches. There are online resources and repair manuals specific to the 1991 Mazda 626 that can show you how to do this safely.
* Try the switches in different positions. Sometimes a faulty switch can be improved with vigorous operation (not always a lasting fix).
* Wiring:
* Visual inspection: Look for broken, frayed, or corroded wires in the door harnesses and the wiring running between the doors and the body. Pay close attention to areas where the wires flex frequently.
* Continuity testing: A multimeter can be used to test the continuity of the wiring from the switch to the motor.
* Common areas for wire damage: The rubber boots that protect the wiring harness where it enters the door are frequent failure points.
* Window Regulators:
* Inspect the regulator: This is the mechanical part that moves the window. If a window moves slowly or makes grinding noises, the regulator itself may be worn, broken, or jammed. Access to the regulator requires removing the door panel.
* Test the motor (if accessible): If you can access the motor, you may be able to test it directly with a 12V power source (be extremely careful when doing this).
* Power Window Motor:
* Common failure point: The power window motor is the most common culprit. These can burn out or become mechanically seized.
* Testing the motor often requires advanced testing equipment or removal of the motor.
3. Resources:
* Repair Manuals: A Haynes or Chilton repair manual for your specific year and model Mazda 626 will provide detailed diagrams and troubleshooting guides.
* Online Forums: Search online forums dedicated to Mazda 626s. You might find someone who has encountered the same problem and has a solution.
* Automotive Professionals: If you lack experience with electrical systems or are not comfortable troubleshooting on your own, consider taking it to a qualified mechanic.
Important Safety Precautions:
* Disconnect the negative battery terminal before working on any electrical components.
* Be careful when working with sharp objects and when removing door panels.
* Always use the correct amperage fuses.
By systematically checking these areas, you should be able to identify the source of the problem with your power windows. Remember to always consult a repair manual for detailed diagrams and specific instructions for your vehicle.
