Introduction:
The B2220 diagnostic trouble code (DTC) indicates an issue with the rear window motor circuit, specifically that the current feedback signal from the window motor driver is exceeding the expected range. This often points to a problem within the motor itself, the wiring harness, or the window motor driver module. Addressing this code promptly is crucial to restore proper window operation and prevent potential damage to related electrical components.
| Symptom/Cause/Action | Description | Possible Solutions |
|---|---|---|
| Symptom: Window Does Not Operate | The rear window fails to move up or down when the switch is activated. | Check the window switch itself for proper function. Inspect the window motor for physical damage or obstruction. * Verify the wiring harness and connectors for corrosion, damage, or loose connections. |
| Symptom: Intermittent Window Operation | The rear window operates sporadically, sometimes working and sometimes not. | Examine the window motor for worn brushes or internal damage. Check the wiring harness for intermittent shorts or open circuits, especially near hinges and points of movement. * Test the window motor driver module for proper operation and signal output. |
| Cause: Faulty Window Motor | The window motor itself is drawing excessive current due to internal wear, damage, or binding. | * Replace the window motor with a new or refurbished unit. Ensure the replacement motor is compatible with the vehicle's make, model, and year. |
| Cause: Short Circuit in Wiring | A short circuit in the wiring harness connecting the window motor and the window motor driver module is causing excessive current draw. | Visually inspect the entire wiring harness for damage, chafing, or exposed wires. Use a multimeter to check for continuity between the power wire and ground. * Repair or replace any damaged wiring. |
| Cause: Open Circuit in Wiring | A break in the wiring harness prevents the necessary current from reaching the window motor. | Use a multimeter to check for continuity along the entire length of the wiring harness between the motor and the control module. Repair or replace any broken wires. |
| Cause: Faulty Window Motor Driver Module | The window motor driver module is malfunctioning and providing incorrect current feedback or failing to regulate current properly. | Test the window motor driver module using a diagnostic scan tool to check for proper operation and signal output. Replace the window motor driver module with a new or refurbished unit. Ensure the replacement module is properly programmed (if required). |
| Cause: Binding Window Mechanism | The window mechanism is binding or obstructed, causing the motor to work harder and draw more current. | Inspect the window tracks and guides for debris, dirt, or damage. Lubricate the window tracks and guides with a silicone-based lubricant. * Repair or replace any damaged window mechanism components. |
| Cause: Corroded Connectors | Corrosion on the electrical connectors in the window motor circuit increases resistance and can lead to inaccurate current feedback. | Disconnect the electrical connectors in the window motor circuit. Clean the connectors with a wire brush or electrical contact cleaner. * Apply dielectric grease to the connectors before reassembling. |
| Action: Check Window Switch | Verify the window switch is functioning correctly by testing its continuity and signal output. | Use a multimeter to check the continuity of the window switch in both the up and down positions. If the switch is faulty, replace it with a new unit. |
| Action: Inspect Wiring Harness | Thoroughly examine the wiring harness for any signs of damage, such as cuts, abrasions, or corrosion. | Pay close attention to areas where the wiring harness is exposed to movement or vibration. Repair or replace any damaged wiring. |
| Action: Test Window Motor | Test the window motor directly by applying power and ground to its terminals. | * If the motor does not operate or operates erratically, it is likely faulty and needs to be replaced. |
| Action: Check for Obstructions | Ensure that the window is not being obstructed by anything, such as debris or misaligned seals. | * Remove any obstructions that are preventing the window from moving freely. |
| Action: Clear DTCs | After addressing the underlying cause of the B2220 code, clear the DTCs using a diagnostic scan tool. | * Verify that the code does not return after clearing it. |
| Action: Recalibrate Window Motor (If Required) | Some vehicles require recalibration of the window motor after replacement or repair. | * Refer to the vehicle's service manual for the proper recalibration procedure. |
| Related DTCs: | Other codes related to window motor operation or electrical circuits. | Addressing these related codes might be necessary to resolve the B2220. Examples include codes for the power window master switch, the body control module (BCM), or other window motor circuits. |
| Affected Systems: | Power Windows, Body Control Module (BCM), Electrical System | Understanding the interaction between these systems helps pinpoint the root cause. |
| Tools Needed: | Multimeter, Diagnostic Scan Tool, Wire Strippers, Crimpers, Electrical Contact Cleaner, Silicone Lubricant | Having the right tools is essential for accurate diagnosis and repair. |
Detailed Explanations
Symptom: Window Does Not Operate: This indicates a complete failure of the rear window to respond to switch commands. The issue could stem from a lack of power to the motor, a faulty motor, a broken switch, or a completely disrupted circuit.
Symptom: Intermittent Window Operation: This describes a situation where the window works sometimes but fails at other times. This is often caused by loose connections, failing components (like the motor brushes wearing down), or intermittent shorts in the wiring.
Cause: Faulty Window Motor: The window motor is responsible for physically moving the window up and down. Over time, the motor can wear out, the brushes can become worn, or the internal components can become damaged, leading to excessive current draw and triggering the B2220 code.
Cause: Short Circuit in Wiring: A short circuit occurs when the power wire comes into contact with ground before reaching the window motor. This creates a path of very low resistance, causing a large amount of current to flow, which can trigger the current feedback exceeded error.
Cause: Open Circuit in Wiring: An open circuit occurs when there is a break in the wiring, preventing the current from reaching the window motor. While this might seem counterintuitive to a "current feedback exceeded" error, a faulty driver module sensing the lack of expected current flow could misinterpret the situation. It's less common, but possible.
Cause: Faulty Window Motor Driver Module: The window motor driver module controls the operation of the window motor, including regulating the current flow and providing feedback to the vehicle's computer. A faulty module can provide incorrect current feedback, mismanage current regulation, or fail completely, leading to the B2220 code.
Cause: Binding Window Mechanism: If the window mechanism is binding due to dirt, debris, or damage, the motor will have to work harder to move the window. This increased effort results in a higher current draw, which can trigger the B2220 code.
Cause: Corroded Connectors: Corrosion on electrical connectors creates resistance, which impedes the flow of current. This increased resistance can also lead to inaccurate current readings and trigger the B2220 code.
Action: Check Window Switch: The window switch is the primary interface for controlling the window. A faulty switch can prevent the window from operating or send incorrect signals to the window motor driver module. Testing the switch ensures it's functioning correctly.
Action: Inspect Wiring Harness: A thorough inspection of the wiring harness is crucial to identify any signs of damage, such as cuts, abrasions, or corrosion. These damages can cause short circuits, open circuits, or increased resistance, all of which can contribute to the B2220 code.
Action: Test Window Motor: Testing the window motor directly by applying power and ground helps determine if the motor itself is functioning correctly. If the motor fails to operate or operates erratically, it's likely faulty and needs to be replaced.
Action: Check for Obstructions: Ensuring that the window is not being obstructed by anything is a simple but important step. Obstructions can cause the motor to work harder, drawing more current and triggering the B2220 code.
Action: Clear DTCs: After addressing the underlying cause of the B2220 code, clearing the DTCs using a diagnostic scan tool is essential. This resets the system and allows you to verify that the code does not return.
Action: Recalibrate Window Motor (If Required): Some vehicles require recalibration of the window motor after replacement or repair. This recalibration process helps the system learn the new motor's characteristics and ensure proper operation. Refer to the vehicle's service manual for the specific recalibration procedure.
Related DTCs: Often, the B2220 code isn't a standalone issue. Other related codes can provide clues to a larger problem. For example, a code related to the body control module (BCM) might indicate a problem with the overall electrical system that's affecting the window motor circuit.
Affected Systems: The power window system, the body control module (BCM), and the overall electrical system are all interconnected. A problem in one system can affect the others. Understanding these interactions helps pinpoint the root cause of the B2220 code.
Tools Needed: A multimeter is essential for checking voltage, continuity, and resistance in the electrical circuits. A diagnostic scan tool is needed to read and clear DTCs. Wire strippers and crimpers are necessary for repairing or replacing damaged wiring. Electrical contact cleaner helps remove corrosion from connectors, and silicone lubricant helps keep the window mechanism operating smoothly.
Frequently Asked Questions
What does the B2220 code mean? It indicates that the rear window motor driver circuit is reporting excessive current feedback. This suggests a problem with the motor, wiring, or driver module.
Can I fix the B2220 code myself? It depends on your mechanical and electrical skills. Simple checks like wiring inspection and lubrication are DIY-friendly, but more complex diagnostics and repairs might require a professional.
How much does it cost to fix the B2220 code? The cost varies depending on the cause. A simple wiring repair might be inexpensive, while replacing the window motor or driver module can be more costly.
Will the B2220 code affect other systems in my car? Potentially. The power window system is often integrated with other systems, so a fault in the window circuit might indirectly affect other functions.
Is it safe to drive with the B2220 code? It's generally safe, but the inoperative window might be inconvenient. Address the issue as soon as possible to prevent further damage or potential safety concerns.
Conclusion:
The B2220 code signals a problem with the rear window motor circuit, specifically excessive current feedback. Thorough diagnostics, including checking the motor, wiring, and driver module, are necessary for accurate problem identification and resolution.