B1573 – OBD-II DTC

OBD-II DTC B1573 – Door Ajar LR Circuit Short To Battery

DTC B1573 meaning

DTC B1573 refers to a diagnostic trouble code indicating a “Door Ajar LR Circuit Short To Battery.” This code is generated when the onboard diagnostic system detects an electrical issue in the left rear door ajar switch circuit. Specifically, it suggests that the circuit is shorted to the battery voltage, which may cause the vehicle’s system to incorrectly interpret the door’s status.

DTC B1573 symptoms

Common symptoms associated with DTC B1573 may include:

• Illumination of the warning light on the dashboard.
• Inconsistent door ajar alerts, even when the door is closed.
• Power door locks may not function properly.
• Interior lights may remain on or not function as expected.

DTC B1573 causes

Several factors can lead to the occurrence of DTC B1573, including:

• A short circuit in the wiring of the left rear door ajar switch.
• Faulty door ajar switch itself.
• Corroded or damaged connectors in the door wiring harness.
• Issues with the vehicle’s body control module (BCM).

DTC B1573 seriousness

The seriousness of DTC B1573 can vary. While it may not prevent the vehicle from operating, it can lead to safety concerns, such as:

• Interior lights remaining on, which can drain the battery.
• Inability to determine if a door is actually ajar, potentially leading to accidents.

It is advisable to address this code promptly to ensure proper vehicle operation and safety.

How to diagnose DTC B1573

To diagnose DTC B1573, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the code.
2. Inspect the left rear door ajar switch and wiring for visible damage or corrosion.
3. Check the continuity of the wiring between the switch and the BCM.
4. Test the door ajar switch for proper operation using a multimeter.
5. Examine the BCM for any fault codes or issues.

How to fix DTC B1573 step-by-step instructions

To fix DTC B1573, follow these steps:

1. Disconnect the vehicle’s battery to ensure safety.
2. Inspect and repair any damaged wiring or connectors in the left rear door circuit.
3. Replace the door ajar switch if it is found to be faulty.
4. Reconnect the battery and clear any stored codes using an OBD-II scanner.
5. Test the system to ensure the issue is resolved and the code does not return.

How to erase DTC B1573

To erase DTC B1573, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the ignition without starting the engine.
3. Navigate to the “Erase Codes” or “Clear Codes” option on the scanner.
4. Confirm the action to clear the trouble codes.
5. Disconnect the scanner and start the vehicle to check if the code reappears.

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