B1379 Code Meaning, Symptoms, Causes and How to Fix

The B1379 code indicates a potential electrical system problem in a vehicle. It means that the IGNITION 3 is not active after IGNITION 1 has been active for 20 seconds.

Symptoms may include difficulty starting the vehicle or the engine not turning over.

Possible causes of this code include a malfunctioning Body Control Module (BCM) or Instrument Panel Cluster (IPC), as well as damaged wiring harnesses or connectors.

To fix the issue, it is recommended to seek professional assistance for proper diagnosis and repair.

What does it mean

The B1379 code indicates a problem with the vehicle's ignition system. It can be caused by a faulty ignition switch or other issues like a faulty BCM or poor electrical connections.

A thorough inspection of the wiring harness, connectors, and components is needed to determine the exact cause. Seek professional help for diagnosis and repair.

what are the symptoms

The symptoms of the B1379 code are typically indicated by the Engine Light or the Service Engine Soon Warning Light being turned on.

Ignoring this code can have the following consequences:

1. Important vehicle information may be lost as the Instrument Panel Cluster (IPC) may not work properly. This means the driver won't have access to crucial data like speed, fuel level, or engine temperature.
2. The Body Control Module (BCM), which controls various electrical functions in the vehicle, may be affected by the B1379 code. Ignoring it can cause issues with power windows, door locks, or lighting systems.
3. The performance of the vehicle's diagnostic system can also be impacted by the B1379 code. Ignoring it may make it difficult to accurately diagnose and fix other potential problems in the vehicle.
4. Ignoring the B1379 code can also pose safety risks as the Service Vehicle Soon indicator may not function properly. This indicator warns about various vehicle malfunctions, and disregarding it can put the driver and passengers in danger.

To ensure the vehicle functions properly and to avoid any safety hazards, it is important to address the B1379 code promptly.

What are the causes

Possible causes of the B1379 code may include:

1. Faulty Body Control Module (BCM): The BCM may not be working properly, which can trigger the B1379 code.
2. Open or shorted BCM harness: A problem with the wiring in the BCM harness can cause the code to appear.
3. Poor electrical connection in the BCM circuit: If there is a weak or faulty connection in the BCM circuit, it can activate the B1379 code.
4. Faulty Instrument Panel Cluster (IPC): A malfunctioning IPC can also be a potential cause of the B1379 code.

To diagnose the B1379 code, follow these steps:

1. Check the possible causes mentioned above.
2. Visually inspect the related wiring harness and connectors for any damage.
3. Look for broken, bent, pushed out, or corroded connector pins.
4. Seek professional assistance if needed.

Common mistakes in diagnosing the B1379 code include overlooking the IPC as a potential cause and not thoroughly inspecting the wiring harness and connectors for any issues. It is crucial to follow a systematic diagnostic approach and address any underlying problems to effectively resolve the B1379 code.

What Tools are Needed to diagnose

To diagnose the B1379 code effectively, a professional technician will need specific tools and equipment. Here are some ideas about the tools needed for diagnosis:

1. Diagnostic Tools: Important equipment for troubleshooting the B1379 code.

• OBD-II Scanner: A tool that retrieves and shows the trouble codes stored in the vehicle's computer system.
• Multimeter: Used to measure voltage, resistance, and continuity in electrical circuits.
• Wiring Diagrams: Essential for tracing and understanding the electrical connections and components related to the B1379 code.
• Test Light: Helps identify power and ground circuits, as well as check for voltage presence.

1. Top Tools for Diagnosing the B1379 Code: A must-have list for mechanics.

• Oscilloscope: Provides a visual representation of electrical signals, allowing for more detailed analysis of circuit behavior.
• Circuit Tester: Helps identify open or short circuits by applying voltage to specific points in the circuit.
• Digital Volt/Ohm Meter (DVOM): Measures voltage, resistance, and current flow, aiding in pinpointing electrical issues.
• Specialty Tools: Depending on the specific vehicle and system, additional tools like terminal release tools or breakout boxes may be needed.

Having these tools will enable technicians to accurately diagnose and troubleshoot the B1379 code, leading to effective repairs and resolution.

How to fix Step by Step

Step 1: Start by checking the possible causes of the DTC B1379 code. These causes include a faulty Body Control Module (BCM), open or shorted BCM harness, or poor electrical connection in the BCM circuit.

Step 2: Visually inspect the wiring harness and connectors related to the BCM for any damage. Look for broken, bent, pushed out, or corroded connector pins.

Step 3: If any damage or issues are found, repair or replace the affected wiring harness or connectors as necessary.

Step 4: Seek professional assistance if needed to ensure accurate diagnosis and repair. They will have the necessary tools and expertise to properly troubleshoot and fix the B1379 code.

Step 5: Ignoring the B1379 code can lead to potential consequences such as the engine light staying on or other unidentified symptoms. It is important to address the issue promptly to prevent further damage or potential safety hazards.

What are the Common Diagnosis Mistakes

Common diagnosis mistakes when dealing with the B1379 code can result in ineffective repairs and potential misdiagnosis. To prevent the reoccurrence of DTC B1379 and avoid common misconceptions about the B1379 code, it is important to keep the following points in mind:

1. Thoroughly inspect the related wiring harness and connectors: Perform a visual inspection to check for any signs of damage or corrosion. Look for broken, bent, pushed out, or corroded connector pins.
2. Check for damaged components: It is essential to inspect the Body Control Module (BCM) and Instrument Panel Cluster (IPC) for any faults or malfunctions.
3. Seek professional assistance when needed: If the diagnosis becomes complex or if you are unsure about the repair process, it is advisable to seek the help of a professional technician who has expertise in dealing with the B1379 code.
4. Address underlying causes: Simply clearing the code without addressing the underlying cause can result in the reoccurrence of DTC B1379. It is important to identify and fix the root cause to prevent the code from coming back.

What is the Repair Cost

The repair cost for the B1379 code can vary based on factors like labor rates, location, and vehicle make, model, and engine type. Labor rates at repair shops range between $75 and $150 per hour, with diagnosis time typically taking around 1.0 hour.

However, costs may vary depending on location and vehicle specifications. Consult a professional technician or repair shop for a more accurate estimation.

Can I drive safely with this code?

Driving with the B1379 code can be unsafe. It indicates a fault with the Body Control Module (BCM) or Instrument Panel Cluster (IPC), affecting gauges and warning lights.

A thorough inspection of the BCM and IPC, including wiring and connectors, is needed for accurate diagnosis. Seek professional assistance for proper repair.

Conclusion

In conclusion, the B1379 code indicates a potential issue within the vehicle's electrical system, specifically the IGNITION 3 not being active after IGNITION 1 for 20 seconds.

Symptoms include the SERVICE VEHICLE SOON indicator illuminating and a check gauges chime sounding.

Possible causes include a faulty Body Control Module (BCM) or Instrument Panel Cluster (IPC), as well as wiring harness or connector damage.

Professional assistance may be required for diagnosis and repair, and the cost can vary depending on factors such as labor rates and vehicle specifications.