B1245 – OBD-II DTC

OBD-II DTC B1245 – Wiper Rear Motor Run Relay Circuit Short to Battery

DTC B1245 meaning

DTC B1245 refers to a diagnostic trouble code indicating a short circuit in the rear wiper motor run relay circuit to the battery. This code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various vehicle components and systems for faults. When the system detects that the rear wiper motor run relay circuit is shorted to battery voltage, it triggers this specific code, alerting the technician to a potential electrical issue.

DTC B1245 symptoms

Common symptoms associated with DTC B1245 may include:

• Rear wiper motor not functioning
• Rear wiper motor running continuously
• Blown fuses related to the rear wiper system
• Inoperative rear wiper switch
• Dashboard warning lights illuminated

DTC B1245 causes

Several factors can lead to the occurrence of DTC B1245, including:

• Short circuit in the wiring harness
• Faulty rear wiper motor
• Defective rear wiper motor run relay
• Corroded or damaged connectors
• Issues with the vehicle’s body control module (BCM)

DTC B1245 seriousness

DTC B1245 can be considered a moderate to serious issue, primarily because it affects the functionality of the rear wiper system. While it may not prevent the vehicle from operating, it can lead to visibility issues in inclement weather, which poses a safety risk. Additionally, if left unaddressed, the underlying electrical problems could potentially lead to further damage to the vehicle’s electrical system.

How to diagnose DTC B1245

To diagnose DTC B1245, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the DTC.
2. Inspect the rear wiper motor and its wiring for visible damage or corrosion.
3. Check the rear wiper motor run relay for proper operation.
4. Test the voltage and ground at the rear wiper motor connector.
5. Examine the body control module (BCM) for any faults or issues.
6. Perform continuity tests on the wiring harness to identify any shorts.

How to fix DTC B1245 step-by-step instructions

To fix DTC B1245, 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 in the rear wiper motor circuit.
3. Replace the rear wiper motor if it is found to be faulty.
4. Test and, if necessary, replace the rear wiper motor run relay.
5. Reconnect the battery and clear the DTC using an OBD-II scanner.
6. Test the rear wiper system to ensure proper operation.

How to erase DTC B1245

To erase DTC B1245, 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 DTC menu on the scanner and select the option to erase or clear 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 reappear.

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