B1328 – OBD-II DTC

OBD-II DTC B1328 – Passenger Door Ajar Circuit Open

DTC B1328 meaning

DTC B1328 refers to a diagnostic trouble code indicating an issue with the passenger door ajar circuit. This code is triggered when the vehicle’s onboard diagnostic system detects an open circuit in the passenger door’s ajar switch, which is responsible for signaling whether the door is closed or open. The system relies on this information to manage various functions, including interior lighting and alarm systems.

DTC B1328 symptoms

Common symptoms associated with DTC B1328 may include:

• Illuminated warning lights on the dashboard
• Interior lights remaining on when the vehicle is off
• Chimes or alerts indicating the door is ajar
• Inconsistent operation of power door locks

DTC B1328 causes

Several factors can lead to the triggering of DTC B1328, including:

• Faulty passenger door ajar switch
• Wiring issues, such as frayed or broken wires
• Corrosion or poor connections in the door harness
• Faulty body control module (BCM)

DTC B1328 seriousness

The seriousness of DTC B1328 can vary. While it may not pose an immediate safety risk, it can lead to inconveniences such as:

• Interior lights draining the battery
• Inability to lock the doors properly
• Potential for increased wear on electrical components

Addressing this issue promptly is advisable to avoid further complications.

How to diagnose DTC B1328

To diagnose DTC B1328, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the code.
2. Inspect the passenger door ajar switch for physical damage or wear.
3. Check the wiring and connectors for signs of corrosion or damage.
4. Test the continuity of the circuit from the switch to the BCM.
5. Examine the BCM for any fault codes or issues.

How to fix DTC B1328 step-by-step instructions

To fix DTC B1328, follow these steps:

1. Repair or replace the passenger door ajar switch if faulty.
2. Fix any damaged wiring or connectors found during inspection.
3. Clean any corrosion on connectors and ensure a secure fit.
4. If necessary, replace the body control module.
5. Clear the DTC using an OBD-II scanner and test the system.

How to erase DTC B1328

To erase DTC B1328, perform the following:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Access the trouble codes menu on the scanner.
3. Select the option to clear or erase codes.
4. Confirm the action and wait for the scanner to complete the process.
5. Disconnect the scanner and start the vehicle to ensure the code does not return.

Recommended tools for OBD-II diagnostics

Explore our expert picks: The Best OBD2 Scanners for 2025

Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter

Some of the links on this page may be affiliate links, which means we may earn a small commission if you make a purchase. This helps us keep our DTC database up to date and provide valuable content for free. We only recommend products that we have tested and believe to be the best in their class.