The diagnostic trouble code (DTC) B3713 indicates a problem within the rear washer motor circuit, specifically that the Body Control Module (BCM) is detecting a voltage higher than expected on the input circuit for the rear washer motor. This can prevent the rear washer from functioning correctly and may indicate a fault in the wiring, the motor itself, or the BCM. Understanding the potential causes and diagnostic steps is crucial for efficient troubleshooting.
This issue can be frustrating for vehicle owners, as it impacts visibility and safety, especially during inclement weather. A malfunctioning rear washer system can obscure the rear window, making it difficult to see traffic behind the vehicle. Properly diagnosing and resolving the B3713 code is essential for restoring full functionality to the rear washer system.
| Component/Symptom | Possible Cause | Action/Explanation |
|---|---|---|
| DTC Definition | Rear Washer Motor Input Circuit High (BCM) | This means the BCM is reading an abnormally high voltage on the rear washer motor control circuit. This typically implies an open circuit or a short to voltage. |
| Common Symptoms | Rear washer not working, Rear washer motor not activating, Intermittent rear washer operation, B3713 DTC present | These are direct indicators of a problem within the rear washer system. |
| BCM (Body Control Module) | Faulty BCM | The BCM is the central control unit for many vehicle functions, including the rear washer. A failing BCM can misread or mismanage the rear washer signal. |
| Wiring Harness/Connectors | Open circuit in the wiring harness, Short to voltage in the wiring harness, Corroded or loose connectors, Damaged wiring insulation | These are common issues that can disrupt the electrical signal to the rear washer motor. Inspect for breaks, corrosion, or shorts. |
| Rear Washer Motor | Internal short to voltage in the motor, Open circuit in the motor winding | While the DTC specifies a "high" reading, a faulty motor can sometimes cause this. Internal shorts or opens can affect the circuit voltage. |
| Ground Connection | Poor ground connection to the rear washer motor, Poor ground connection to the BCM | Insufficient grounding can cause erratic voltage readings and prevent the motor from operating correctly. |
| Fuse/Relay (If Applicable) | Blown fuse or faulty relay (check vehicle-specific wiring diagrams) | While less common for a "high" reading, a blown fuse or faulty relay supplying power to the circuit can sometimes indirectly cause this code. |
| Diagnostic Tools | Scan tool, Multimeter, Wiring diagram | These are essential for diagnosing electrical issues. The scan tool reads the DTC, the multimeter tests voltage and continuity, and the wiring diagram helps trace the circuit. |
| Troubleshooting Steps | Verify the DTC with a scan tool, Inspect wiring and connectors, Test the rear washer motor, Test the BCM output, Check ground connections | These are the systematic steps for pinpointing the cause of the B3713 code. |
| Voltage Readings | High voltage reading on the rear washer motor control wire when the motor is supposed to be off | This confirms the "circuit high" condition. A normal reading should be close to 0V when the motor is off. |
| Resistance Readings | High resistance or open circuit in the wiring harness or motor | Use a multimeter to check for continuity between the BCM and the rear washer motor. A high resistance indicates a break in the circuit. |
| Location of Components | BCM location (typically under the dash or in the center console), Rear washer motor location (typically near the rear window or tailgate) | Knowing the location of these components is crucial for inspection and testing. Refer to the vehicle's service manual. |
| Impact on Vehicle Operation | Rear washer inoperative, Possible other electrical issues if the BCM is affected | The primary impact is the lack of rear washer functionality. In rare cases, a faulty BCM can cause other electrical problems. |
| Severity | Low to Medium | While not immediately dangerous, a malfunctioning rear washer impairs visibility and can be a safety concern. |
| Related DTCs | Other BCM-related DTCs, Related washer system DTCs | If other codes are present, address them first as they may be contributing to the B3713 code. |
| Specific Vehicle Makes/Models | Varies depending on vehicle manufacturer and model year | This code is not unique to any specific brand, but implementation and troubleshooting steps may vary. Consult the vehicle's service manual. |
| Repair Costs | Varies depending on the cause, from minor wiring repairs to BCM replacement | Simple wiring repairs are relatively inexpensive, while BCM replacement can be costly. |
| DIY Difficulty | Moderate | Troubleshooting electrical issues requires some technical knowledge and experience. |
| Preventative Measures | Regular vehicle maintenance, Inspecting wiring and connectors for corrosion | These measures can help prevent electrical problems from developing. |
| Software Updates | BCM software updates (rarely, but possible) | In some cases, a BCM software update can resolve communication issues. Check for available updates from the manufacturer. |
| Aftermarket Accessories | Interference from aftermarket accessories (e.g., improperly installed trailer wiring) | Aftermarket accessories can sometimes interfere with the vehicle's electrical system. |
| Environmental Factors | Exposure to moisture or extreme temperatures | These factors can accelerate corrosion and damage to wiring and connectors. |
| Vehicle History | History of electrical problems | If the vehicle has a history of electrical issues, it may be more prone to developing this type of problem. |
| Warranty Coverage | May be covered under the vehicle's warranty (check warranty terms and conditions) | Check the vehicle's warranty terms to see if the repair is covered. |
| Voltage Drop Testing | Used to identify areas of excessive resistance in the wiring harness | Voltage drop testing can help pinpoint the exact location of a wiring fault. |
| BCM Reprogramming | May be required after replacing the BCM | A new BCM often needs to be programmed to the vehicle's specific configuration. |
| CAN Bus Communication | Problems with CAN bus communication can affect BCM operation | The BCM communicates with other modules via the CAN bus. Problems with CAN bus communication can lead to various issues, including false DTCs. |
| Component Testing | Testing individual components (e.g., rear washer motor) to isolate the fault | Component testing involves using a multimeter to check the resistance, voltage, and continuity of individual components. |
| Short to Power | A wire in the rear washer motor circuit is making contact with a power source | This is a common cause of the B3713 code. Look for chafed or damaged wires that are touching a power source. |
| Open Circuit | A break in the rear washer motor circuit | An open circuit prevents the rear washer motor from receiving power. Use a multimeter to check for continuity in the wiring harness. |
Detailed Explanations
DTC Definition: The DTC B3713 specifically indicates that the Body Control Module (BCM) is detecting an abnormally high voltage level on the input circuit that controls the rear washer motor. This suggests an electrical fault that needs to be investigated. The BCM expects to see a low voltage when the rear washer is off and a specific voltage when activated. A "high" reading when the motor is off is the problem.
Common Symptoms: The most obvious symptom is a rear washer that doesn't work. This could manifest as no fluid spraying, the motor not making any noise, or intermittent operation. The presence of the B3713 DTC when scanned with a diagnostic tool confirms the electrical issue.
BCM (Body Control Module): The BCM is a crucial electronic control unit that manages various vehicle functions, including lighting, door locks, and in this case, the rear washer system. If the BCM is faulty, it can misinterpret signals or fail to send the correct commands to the rear washer motor.
Wiring Harness/Connectors: The wiring harness and connectors are the pathways that carry electrical signals to and from the rear washer motor. Damage such as open circuits (broken wires), shorts to voltage (wire touching a power source), corrosion, or loose connections can disrupt the signal and trigger the B3713 code. Careful inspection of these components is essential.
Rear Washer Motor: While the DTC suggests a "high" reading, the rear washer motor itself can be the source of the problem. An internal short to voltage within the motor or an open circuit in its windings can affect the voltage readings on the control circuit.
Ground Connection: A poor ground connection can cause a variety of electrical problems, including incorrect voltage readings. Ensure that the rear washer motor and the BCM have solid, clean ground connections to the vehicle's chassis.
Fuse/Relay (If Applicable): While less likely to cause a "high" reading directly, a blown fuse or a faulty relay that supplies power to the rear washer motor circuit could indirectly contribute to the problem. Consult the vehicle's wiring diagram to identify any relevant fuses or relays.
Diagnostic Tools: A scan tool is necessary to read the B3713 DTC and any other related codes. A multimeter is essential for testing voltage, continuity, and resistance in the wiring harness and components. A wiring diagram provides a visual representation of the rear washer motor circuit, aiding in troubleshooting.
Troubleshooting Steps: A systematic approach is key to diagnosing the B3713 code. Start by verifying the DTC with a scan tool. Then, carefully inspect the wiring harness and connectors for damage. Test the rear washer motor and the BCM output using a multimeter. Finally, check all ground connections for proper contact.
Voltage Readings: A high voltage reading on the rear washer motor control wire when the motor is supposed to be off is a key indicator of the problem. A normal reading should be close to 0 volts when the motor is not activated.
Resistance Readings: Use a multimeter to measure the resistance between the BCM and the rear washer motor. A high resistance or an open circuit indicates a break in the wiring harness.
Location of Components: Knowing the location of the BCM and the rear washer motor is crucial for inspection and testing. The BCM is typically located under the dashboard or in the center console, while the rear washer motor is usually near the rear window or tailgate. Refer to the vehicle's service manual for specific locations.
Impact on Vehicle Operation: The primary impact of the B3713 code is the inoperability of the rear washer system. This can impair visibility and be a safety concern, especially during inclement weather.
Severity: The severity of the B3713 code is generally considered low to medium. While not immediately dangerous, a malfunctioning rear washer can compromise safety by reducing visibility.
Related DTCs: If other DTCs are present, especially those related to the BCM or other washer systems, address them first. They may be contributing to the B3713 code.
Specific Vehicle Makes/Models: The B3713 code is not specific to any particular vehicle make or model. However, the implementation of the rear washer system and the troubleshooting steps may vary. Always consult the vehicle's service manual for specific instructions.
Repair Costs: Repair costs can vary depending on the cause of the problem. Simple wiring repairs are relatively inexpensive, while BCM replacement can be a significant expense.
DIY Difficulty: Troubleshooting electrical issues requires some technical knowledge and experience. The DIY difficulty for the B3713 code is considered moderate. If you are not comfortable working with electrical systems, it is best to seek professional help.
Preventative Measures: Regular vehicle maintenance, including inspecting wiring and connectors for corrosion and damage, can help prevent electrical problems from developing.
Software Updates: In rare cases, a BCM software update can resolve communication issues that may be contributing to the B3713 code. Check with the vehicle manufacturer for available updates.
Aftermarket Accessories: Improperly installed aftermarket accessories, such as trailer wiring, can sometimes interfere with the vehicle's electrical system and trigger the B3713 code.
Environmental Factors: Exposure to moisture or extreme temperatures can accelerate corrosion and damage to wiring and connectors, increasing the likelihood of electrical problems.
Vehicle History: If the vehicle has a history of electrical problems, it may be more prone to developing this type of issue.
Warranty Coverage: Check the vehicle's warranty terms and conditions to see if the repair is covered.
Voltage Drop Testing: Used to identify areas of excessive resistance in the wiring harness. It helps pinpoint the exact location of a wiring fault.
BCM Reprogramming: May be required after replacing the BCM. A new BCM often needs to be programmed to the vehicle's specific configuration.
CAN Bus Communication: Problems with CAN bus communication can affect BCM operation. The BCM communicates with other modules via the CAN bus, and problems with this communication can lead to various issues, including false DTCs.
Component Testing: Testing individual components (e.g., rear washer motor) to isolate the fault. Component testing involves using a multimeter to check the resistance, voltage, and continuity of individual components.
Short to Power: A wire in the rear washer motor circuit is making contact with a power source. This is a common cause of the B3713 code. Look for chafed or damaged wires that are touching a power source.
Open Circuit: A break in the rear washer motor circuit. An open circuit prevents the rear washer motor from receiving power. Use a multimeter to check for continuity in the wiring harness.
Frequently Asked Questions
What does the B3713 code mean? It means the Body Control Module (BCM) is detecting a higher-than-expected voltage on the rear washer motor input circuit. This usually points to an electrical fault in the wiring or the motor itself.
How do I fix the B3713 code? Start by inspecting the wiring and connectors for damage, then test the rear washer motor and BCM output with a multimeter. Repair any wiring issues and replace faulty components if necessary.
Can a bad rear washer motor cause this code? Yes, a faulty rear washer motor with an internal short can affect the voltage readings and trigger the B3713 code. Testing the motor is a crucial step in the diagnostic process.
Is it safe to drive with the B3713 code? While not immediately dangerous, a malfunctioning rear washer impairs visibility, especially in bad weather. Address the issue as soon as possible for safety.
Do I need a special tool to diagnose this code? Yes, a scan tool is needed to read the DTC, and a multimeter is essential for testing the wiring and components. A wiring diagram for your vehicle will also be helpful.
Conclusion
The B3713 DTC indicates a "Rear Washer Motor Input Circuit High (BCM)" issue, usually stemming from wiring problems, a faulty rear washer motor, or potentially a malfunctioning BCM. By systematically inspecting the wiring, testing components with a multimeter, and consulting the vehicle's service manual, you can effectively diagnose and resolve this issue, restoring full functionality to your rear washer system.