B1788 – OBD-II DTC

OBD-II DTC B1788 – Mirror Passenger Down Circuit Short To Battery

DTC B1788 meaning

DTC B1788 refers to a diagnostic trouble code indicating a short circuit in the passenger side mirror’s down circuit to the battery. This code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various vehicle components for faults. When the system detects an abnormal voltage or resistance in the circuit responsible for lowering the passenger side mirror, it triggers this code.

DTC B1788 symptoms

Common symptoms associated with DTC B1788 may include:

• The passenger side mirror may not respond when attempting to adjust it downwards.
• Other mirror functions may work intermittently or not at all.
• Dashboard warning lights may illuminate, indicating a fault in the mirror system.
• In some cases, the vehicle may exhibit electrical issues related to the mirror circuit.

DTC B1788 causes

Several factors can lead to the occurrence of DTC B1788, including:

• A short circuit in the wiring harness connected to the passenger side mirror.
• Faulty mirror switch or control module.
• Corrosion or damage in the electrical connectors.
• Defective mirror motor that may cause excessive current draw.

DTC B1788 seriousness

The seriousness of DTC B1788 can vary. While it may not affect the vehicle’s overall drivability, it can lead to safety concerns if the passenger side mirror cannot be adjusted properly. Additionally, unresolved electrical issues may lead to further complications in the vehicle’s electrical system.

How to diagnose DTC B1788

To diagnose DTC B1788, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the B1788 code.
2. Inspect the wiring and connectors associated with the passenger side mirror for any visible damage or corrosion.
3. Test the mirror switch for proper operation using a multimeter.
4. Check the mirror motor for functionality by applying direct power to it.
5. Examine the vehicle’s wiring diagram to trace the circuit and identify any potential shorts.

How to fix DTC B1788 step-by-step instructions

To fix DTC B1788, follow these step-by-step instructions:

1. Disconnect the vehicle’s battery to ensure safety while working on the electrical system.
2. Inspect and repair any damaged wiring or connectors found during diagnosis.
3. If the mirror switch is faulty, replace it with a new one.
4. Test the mirror motor and replace it if it is not functioning correctly.
5. Reconnect the battery and clear the DTC using an OBD-II scanner.
6. Test the passenger side mirror to ensure it operates correctly in all directions.

How to erase DTC B1788

To erase DTC B1788, 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 trouble codes section of the scanner.
4. Select the option to clear or erase the codes.
5. Confirm the action and wait for the scanner to complete the process.
6. Disconnect the scanner and start the vehicle to ensure the code does not reappear.

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