B1774 – OBD-II DTC

OBD-II DTC B1774 – Mirror Driver Up Circuit Open

DTC B1774 meaning

DTC B1774 refers to a diagnostic trouble code indicating an issue with the driver’s side mirror’s up circuit. This code is triggered when the vehicle’s onboard diagnostic system detects an open circuit in the wiring or components associated with the driver’s side mirror adjustment mechanism. The up circuit is responsible for controlling the vertical movement of the mirror, and any disruption can lead to malfunctioning of the mirror’s adjustment features.

DTC B1774 symptoms

Common symptoms associated with DTC B1774 may include:

• The driver’s side mirror does not adjust up or down.
• Other mirror functions may work, but the up movement is unresponsive.
• Intermittent issues with the mirror adjustment controls.
• Possible warning lights on the dashboard related to the mirror system.

DTC B1774 causes

Several factors can lead to the triggering of DTC B1774, including:

• A broken or frayed wire in the mirror adjustment circuit.
• A faulty mirror switch or control module.
• Corrosion or poor connections in the wiring harness.
• Defective mirror motor that fails to respond to commands.

DTC B1774 seriousness

The seriousness of DTC B1774 can vary. While it may not pose an immediate safety risk, it can affect the driver’s ability to adjust the mirror for optimal visibility. This can lead to unsafe driving conditions. It is advisable to address the issue promptly to ensure proper functionality of the vehicle’s mirror system.

How to diagnose DTC B1774

To diagnose DTC B1774, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1774 code.
2. Inspect the wiring and connectors associated with the driver’s side mirror for any visible damage.
3. Test the mirror switch for proper operation using a multimeter.
4. Check for continuity in the up circuit wiring.
5. Examine the mirror motor for functionality.

How to fix DTC B1774 step-by-step instructions

To fix DTC B1774, follow these step-by-step instructions:

1. Disconnect the vehicle’s battery to ensure safety while working on electrical components.
2. Inspect the wiring harness for any signs of damage, such as fraying or breaks.
3. If damage is found, repair or replace the affected wiring.
4. Test the mirror switch and replace it if it is found to be faulty.
5. Check the mirror motor for proper operation and replace it if necessary.
6. Reconnect the battery and clear the DTC using an OBD-II scanner.
7. Test the mirror adjustment functions to ensure they are working correctly.

How to erase DTC B1774

To erase DTC B1774, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the vehicle’s ignition without starting the engine.
3. Navigate to the option to clear or erase trouble codes on the scanner.
4. Confirm the action to erase the DTC.
5. Disconnect the scanner and start the vehicle to ensure the code does not reappear.

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