B1407 Driver Power Window up Circuit Open

Introduction

The B1407 diagnostic trouble code (DTC) indicates a problem within the driver's side power window circuit, specifically related to the "up" functionality. This means the vehicle's computer has detected an open circuit in the wiring or components responsible for raising the driver's side window. Addressing this issue promptly is crucial for convenience, security, and overall vehicle functionality.

Comprehensive Table: B1407 Driver Power Window up Circuit Open

Detailed Explanations

Definition: Driver Power Window Up Circuit Open

This DTC signifies that the vehicle's computer has detected a break in the electrical circuit specifically responsible for raising the driver's side power window. The computer monitors the electrical signals within the circuit and, when it detects a lack of continuity (an "open"), it triggers the B1407 code. This open circuit prevents the necessary electrical current from reaching the power window motor when the "up" switch is activated, hindering the window's ability to move upward.

Symptoms

The most obvious symptom is the inability of the driver's side window to move upward when the "up" switch is engaged. You might also notice that there is no motor noise when attempting to raise the window, indicating that the motor is not receiving power. Importantly, other windows in the vehicle might function normally, as they operate on separate circuits. The power window switch itself might feel loose or unresponsive, and in some cases, the window may work intermittently, suggesting a loose connection or intermittent break in the circuit.

Common Causes

Several factors can lead to an open circuit in the driver's side power window "up" function:

• Faulty Power Window Switch (Driver's Side): The switch is the most common culprit. Over time, the contacts within the switch can become damaged, corroded, or worn, preventing proper electrical contact.
• Broken Wiring: The wiring harness that carries the electrical signals to the window motor is susceptible to damage, especially in the door jamb area where the wires flex with each opening and closing of the door. Cuts, frays, or corrosion can create an open circuit.
• Faulty Power Window Motor: While less common than a switch or wiring issue, the power window motor itself can fail. Internal components can wear out or burn out, preventing the motor from operating.
• Faulty Window Regulator: The regulator is the mechanical mechanism that raises and lowers the window. If it's jammed, damaged, or broken, it can prevent the motor from moving the window, even if the motor is functioning correctly. This can sometimes create a false indication of an electrical problem.
• Blown Fuse: A blown fuse protecting the power window circuit will cut off power to the entire system, including the "up" function.
• Corroded Connectors: Electrical connectors within the power window circuit can corrode over time, especially in humid environments. Corrosion increases resistance and can eventually lead to an open circuit.
• Body Control Module (BCM) Issue: In rare cases, the BCM, which controls various electrical functions in the vehicle, including the power windows, can malfunction and cause the B1407 code. This is usually a last resort diagnosis after ruling out other more common causes.

Diagnostic Steps

Diagnosing the B1407 code requires a systematic approach:

1. Visual Inspection: Begin by carefully inspecting the power window switch, wiring harness, and connectors for any obvious signs of damage, such as broken wires, frayed insulation, or corroded terminals. Pay close attention to the wiring in the door jamb area.
2. Fuse Check: Locate the fuse that protects the power window circuit (consult your vehicle's owner's manual for the fuse location) and inspect it to ensure it's not blown. Replace it if necessary.
3. Switch Testing: Use a multimeter to test the power window switch for continuity. Disconnect the switch and use the multimeter to check for continuity between the appropriate terminals when the switch is in the "up" position. If there is no continuity, the switch is likely faulty.
4. Wiring Testing: Use a multimeter to check for continuity and voltage in the wiring harness. Consult a wiring diagram specific to your vehicle to identify the correct wires to test. Check for continuity between the switch and the motor, and check for voltage at the motor when the switch is activated.
5. Motor Testing: Apply direct power to the window motor to see if it functions. Disconnect the motor from the wiring harness and use jumper wires to connect it directly to the vehicle's battery. If the motor works when powered directly, the problem lies elsewhere in the circuit.
6. Regulator Inspection: Visually inspect the window regulator for damage. Look for broken cables, bent arms, or any other signs of mechanical failure.
7. BCM Diagnosis: If all other components check out, the problem might lie within the BCM. BCM diagnosis and repair often require specialized tools and expertise, so it's best left to a qualified technician.

Tools Required

• Multimeter: Essential for testing continuity and voltage in the electrical circuit.
• Screwdrivers: Needed to remove trim panels and access the power window switch and motor.
• Wire Strippers/Crimpers: Required for repairing or replacing damaged wiring.
• Test Light: A simple tool for checking for power in the circuit.
• Wiring Diagram (specific to the vehicle): Crucial for identifying the correct wires and terminals to test.
• Socket Set: Needed to remove bolts securing the window regulator and motor.
• Pliers: Useful for gripping and manipulating wires and connectors.
• Fuse Puller: Makes it easier to remove fuses without damaging them.

Potential Fixes

• Replace Faulty Power Window Switch: If the switch is found to be faulty, replacing it is usually the easiest solution.
• Repair or Replace Damaged Wiring: Repairing damaged wiring involves splicing in new sections of wire and properly insulating the connections. If the damage is extensive, replacing the entire wiring harness might be necessary.
• Replace Faulty Power Window Motor: If the motor is found to be faulty, replacing it is the best course of action.
• Replace Faulty Window Regulator: If the regulator is damaged, it must be replaced.
• Replace Blown Fuse: Replacing a blown fuse is a simple and inexpensive fix, but it's important to identify the underlying cause of the blown fuse to prevent it from happening again.
• Clean Corroded Connectors: Cleaning corroded connectors with a wire brush or electrical contact cleaner can restore proper electrical flow.
• Reprogram or Replace the BCM (if necessary): BCM issues are complex and often require specialized tools and expertise. Reprogramming or replacing the BCM should be done by a qualified technician.

Related Codes

Understanding related codes can help pinpoint the problem:

• B1406 (Driver Power Window Down Circuit Open): Indicates an open circuit in the "down" function of the driver's side window.
• B1408 (Driver Power Window Up Circuit Short to Ground): Indicates a short circuit to ground in the "up" function of the driver's side window.
• B1409 (Driver Power Window Down Circuit Short to Ground): Indicates a short circuit to ground in the "down" function of the driver's side window.
• Other power window codes specific to other windows: These codes indicate problems with the power windows on other doors in the vehicle.

Severity

The severity of the B1407 code is considered moderate. While it doesn't directly affect the engine or other critical vehicle systems, a malfunctioning power window can compromise security, as the window might be stuck open. It also affects convenience and can be a safety concern in inclement weather.

Estimated Repair Cost

The estimated repair cost varies greatly depending on the cause of the problem:

• Fuse Replacement: Inexpensive (a few dollars).
• Switch or Wiring Repair: Moderately priced (typically between $50 and $200, depending on the extent of the damage and labor costs).
• Motor or Regulator Replacement: More costly (can range from $150 to $500 or more, including parts and labor).
• BCM Issues: Typically the most expensive to diagnose and repair (can easily exceed $500 or even $1000, depending on the complexity of the repair and the cost of the BCM).

Labor costs will also vary depending on the mechanic's hourly rate and the complexity of the repair.

Safety Precautions

• Disconnect the Negative Battery Terminal: Before working on any electrical components, disconnect the negative battery terminal to prevent accidental short circuits.
• Use Proper Safety Glasses and Gloves: Protect your eyes and hands from potential hazards.
• Consult a Wiring Diagram Specific to Your Vehicle: Ensure you are working with the correct wires and terminals.
• Be Careful When Working with Power Tools: Use power tools with caution and follow the manufacturer's instructions.

Frequently Asked Questions

• What does the B1407 code mean? The B1407 code indicates that there is an open circuit in the driver's side power window "up" circuit, preventing the window from going up. This means the electrical connection is broken somewhere.

• Is it safe to drive with a B1407 code? It's generally safe to drive, but the open window can compromise security and comfort. Repair the issue as soon as possible.

• Can I fix the B1407 code myself? Yes, if you have basic mechanical and electrical skills, you can diagnose and repair the problem. However, if you are not comfortable working with electrical systems, it's best to take your vehicle to a qualified mechanic.

• How much will it cost to fix the B1407 code? The cost varies depending on the cause, ranging from a few dollars for a fuse to several hundred dollars for a motor or regulator replacement. Diagnosis by a mechanic will also add to the cost.

• What is the most common cause of the B1407 code? A faulty power window switch or damaged wiring are the most common causes. These components are subjected to wear and tear over time.

Conclusion

The B1407 code points to a break in the driver's side power window "up" circuit, typically caused by a faulty switch, damaged wiring, or a malfunctioning motor. By following a systematic diagnostic process and taking appropriate safety precautions, you can identify and resolve the issue, restoring the functionality of your power window.