Introduction:
The B1337 diagnostic trouble code (DTC) indicates a problem with the Door Ajar circuit, specifically on the Right Rear (RR) door, where there is a short circuit to the battery voltage. This means the electrical circuit responsible for signaling when the right rear door is open or closed is unintentionally connected to a power source, leading to incorrect signals being sent to the vehicle's computer system. This can cause a variety of issues, from a constantly illuminated door ajar warning light to potentially draining the vehicle's battery.
Table: B1337 Door Ajar RR Circuit Short To Battery
| Topic | Description | Potential Consequences |
|---|---|---|
| DTC Definition | B1337: Door Ajar RR (Right Rear) Circuit Short To Battery. This means the door ajar sensor circuit for the right rear door is experiencing an unintended connection to the vehicle's battery voltage. | Continuously illuminated door ajar warning light, potential battery drain, inability to properly lock/unlock the vehicle, malfunctioning security system, potential issues with the vehicle's body control module (BCM). |
| Affected Components | Right Rear Door Ajar Switch/Sensor, Wiring Harness (between the door ajar switch and the BCM), Connectors, BCM (Body Control Module). | Malfunctioning door ajar switch, damaged wiring (frayed, cut, or corroded), loose or corroded connectors, internal failure within the BCM. |
| Common Causes | Damaged wiring in the door jamb (often due to repeated opening and closing of the door), Water intrusion into the door ajar switch or connector, Faulty door ajar switch, Short circuit within the wiring harness, Corrosion on connectors, Damaged or faulty BCM. | Wiring rubbing against metal surfaces, cracked or brittle insulation, improper sealing of the door ajar switch, corrosion caused by road salt or moisture, internal short circuit within the switch, loose connectors due to vibration, BCM damage due to electrical surges or water damage. |
| Diagnostic Steps | 1. Visually inspect the wiring and connectors. 2. Check for voltage at the door ajar switch. 3. Test the door ajar switch for proper operation. 4. Perform a continuity test on the wiring harness. 5. Inspect the BCM for damage. 6. Use a scan tool to monitor the door ajar switch signal. | Using a multimeter to measure voltage and resistance, using a wiring diagram to trace the circuit, using a scan tool to read diagnostic data, checking for corrosion or damage on components, physically inspecting the wiring harness for breaks or shorts. |
| Possible Solutions | Repair or replace damaged wiring, Replace faulty door ajar switch, Clean or replace corroded connectors, Repair or replace the wiring harness, Replace the BCM (requires programming). | Splicing and insulating damaged wires, replacing the door ajar switch with a new one, cleaning corroded connectors with electrical contact cleaner, replacing sections of the wiring harness with new wire, replacing the BCM and programming it to the vehicle. |
| Related Symptoms | Door ajar light illuminated when the door is closed, Interior lights staying on, Security system malfunctions, Power door locks not working correctly, Battery drain. | Intermittent door ajar warning, false alarms from the security system, difficulty locking or unlocking the doors, a dead battery after the vehicle has been sitting for a period of time. |
| Tools Required | Multimeter, Scan Tool, Wiring Diagram, Wire Strippers, Crimpers, Electrical Tape, Contact Cleaner, Test Light. | Tools needed to diagnose electrical issues, repair wiring, and test components. A scan tool is crucial for reading diagnostic codes and monitoring sensor data. |
| Safety Precautions | Disconnect the negative battery terminal before working on the electrical system, Use caution when working with electrical components, Consult a wiring diagram before making any repairs, Wear appropriate safety gear (gloves, eye protection). | Preventing electrical shock, avoiding damage to electrical components, ensuring proper repairs, protecting oneself from injury. |
| BCM Programming | If the BCM needs to be replaced, it will require programming to the vehicle's VIN (Vehicle Identification Number) and other specific settings. This typically requires specialized equipment and software. | Ensuring the new BCM is properly configured to work with the vehicle's other systems, preventing communication errors, ensuring proper functionality of all vehicle systems controlled by the BCM. |
Detailed Explanations:
DTC Definition: The B1337 code specifically identifies a short to battery voltage within the door ajar circuit for the right rear door. The "short to battery" aspect indicates that the wiring or the door ajar switch itself is allowing voltage from the vehicle's battery to flow into the circuit when it shouldn't. This incorrect voltage signal is then interpreted by the Body Control Module (BCM) as the door being open, even when it's closed.
Affected Components: The components most likely involved are the door ajar switch located within the right rear door latch mechanism, the wiring harness connecting the switch to the BCM, any connectors within that wiring harness, and potentially the BCM itself. The door ajar switch is a simple on/off switch that closes the circuit when the door is open. The wiring harness provides the electrical pathway for the signal. The connectors provide connection points within the wiring. The BCM receives and interprets the signal from the door ajar switch.
Common Causes: The most frequent cause is damage to the wiring in the door jamb. Constant opening and closing of the door can cause the wires to flex and eventually break or wear through the insulation, leading to a short. Water intrusion into the door ajar switch or connector can also cause corrosion and short circuits. A faulty door ajar switch itself can also cause this issue. Less common causes include a short circuit within the wiring harness (due to chafing or damage) and a damaged BCM.
Diagnostic Steps: The diagnostic process starts with a visual inspection of the wiring and connectors associated with the right rear door ajar switch, looking for any signs of damage or corrosion. Next, use a multimeter to check for voltage at the door ajar switch connector with the door closed. If voltage is present when it shouldn't be, it confirms a short to battery. The door ajar switch itself should be tested for proper operation using a multimeter. A continuity test on the wiring harness can help identify any breaks or shorts in the wiring. The BCM should be inspected for any visible damage. Finally, a scan tool can be used to monitor the door ajar switch signal and see if it is behaving as expected.
Possible Solutions: If damaged wiring is found, it needs to be repaired or replaced. This may involve splicing in new sections of wire and properly insulating the connections. If the door ajar switch is faulty, it should be replaced. Corroded connectors should be cleaned with electrical contact cleaner or replaced if severely damaged. If the wiring harness is damaged beyond repair, it needs to be replaced. In rare cases, the BCM may be faulty and require replacement. BCM replacement requires programming to the vehicle's VIN.
Related Symptoms: Besides the B1337 code itself, common symptoms include the door ajar light remaining illuminated even when the door is closed, the interior lights staying on, the security system malfunctioning (false alarms), the power door locks not working correctly (especially the right rear door), and potentially a battery drain if the interior lights remain on for extended periods.
Tools Required: A multimeter is essential for testing voltage and resistance. A scan tool is needed to read diagnostic codes and monitor sensor data. A wiring diagram is crucial for tracing the circuit and identifying the correct wires. Wire strippers and crimpers are necessary for repairing or replacing wiring. Electrical tape or heat shrink tubing is needed to insulate wire splices. Contact cleaner is used to clean corroded connectors. A test light can be helpful for quickly checking for voltage.
Safety Precautions: Always disconnect the negative battery terminal before working on the electrical system to prevent electrical shock. Be careful when working with electrical components to avoid damaging them. Always consult a wiring diagram before making any repairs to ensure that you are working on the correct wires. Wear appropriate safety gear, such as gloves and eye protection.
BCM Programming: If the BCM needs to be replaced, it will require programming. This involves using specialized equipment and software to program the BCM with the vehicle's VIN and other specific settings. This is typically a task best left to a qualified technician with the necessary tools and expertise. Failing to properly program the BCM can result in various vehicle malfunctions.
Frequently Asked Questions:
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What does B1337 mean? It means "Door Ajar Right Rear Circuit Short To Battery" indicating a fault in the door ajar sensor circuit of the right rear door.
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Can I fix B1337 myself? Potentially, if you are comfortable with basic electrical troubleshooting and have the necessary tools. However, if you are unsure, it's best to consult a qualified mechanic.
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Is B1337 a serious problem? It can lead to battery drain and security system issues, so it should be addressed promptly.
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How do I test the door ajar switch? Use a multimeter to check for continuity when the door is open and closed. The switch should have continuity when the door is open and no continuity when the door is closed.
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Will B1337 cause other problems? Yes, it can cause a continuously illuminated door ajar light, interior lights to stay on, and potential security system malfunctions.
Conclusion:
The B1337 code signifies a short to battery in the right rear door ajar circuit, often stemming from wiring damage or a faulty switch. Thorough diagnosis and repair, following the outlined steps, are essential to resolve the issue and prevent further complications.