B1894 – OBD-II DTC

OBD-II DTC B1894 – Wiper Rear Motor Speed Sense Circuit Failure

DTC B1894 meaning

DTC B1894 refers to a diagnostic trouble code indicating a failure in the rear wiper motor speed sense circuit. This code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various vehicle components to ensure proper functionality. The rear wiper motor is responsible for clearing the rear windshield, and the speed sense circuit provides feedback to the vehicle’s control module regarding the motor’s operational speed.

DTC B1894 symptoms

Common symptoms associated with DTC B1894 may include:

• Inoperative rear wiper motor
• Intermittent operation of the rear wiper
• Erratic wiper speed or behavior
• Dashboard warning lights related to the wiper system

DTC B1894 causes

Several factors can lead to the triggering of DTC B1894, including:

• Faulty rear wiper motor
• Damaged or corroded wiring in the speed sense circuit
• Defective wiper control module
• Poor electrical connections or ground issues
• Software glitches in the vehicle’s control system

DTC B1894 seriousness

The seriousness of DTC B1894 can vary. While it may not pose an immediate safety risk, it can affect visibility during inclement weather if the rear wiper is inoperative. It is advisable to address this issue promptly to ensure proper vehicle operation and safety.

How to diagnose DTC B1894

To diagnose DTC B1894, follow these steps:

1. Use an OBD-II scanner to confirm the presence of DTC B1894.
2. Inspect the rear wiper motor and its connections for any visible damage or corrosion.
3. Check the wiring and connectors in the speed sense circuit for continuity and proper grounding.
4. Test the rear wiper motor operation using a multimeter to measure voltage and resistance.
5. Examine the wiper control module for any faults or software issues.

How to fix DTC B1894 step-by-step instructions

To fix DTC B1894, follow these steps:

1. Repair or replace any damaged wiring or connectors in the speed sense circuit.
2. If the rear wiper motor is faulty, replace it with a new or refurbished unit.
3. Ensure all electrical connections are clean and secure.
4. Reprogram or replace the wiper control module if necessary.
5. Clear the DTC using an OBD-II scanner and test the rear wiper operation.

How to erase DTC B1894

To erase DTC B1894, follow these steps:

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 perform a test drive to ensure the code does not reappear.

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