B1817 – OBD-II DTC

OBD-II DTC B1817 – Wiper Rear Motor Down Relay Coil Circuit Short To Ground

DTC B1817 meaning

DTC B1817 refers to a diagnostic trouble code indicating a short circuit to ground in the rear wiper motor down relay coil circuit. This code is part of the On-Board Diagnostics II (OBD-II) system, which monitors various vehicle systems for faults. When the vehicle’s control module detects an abnormal voltage level in the rear wiper motor relay circuit, it triggers this code to alert the technician of a potential issue.

DTC B1817 symptoms

Common symptoms associated with DTC B1817 may include:

• Rear wiper not functioning
• Intermittent operation of the rear wiper
• Wiper motor may run continuously
• Dashboard warning lights may illuminate

DTC B1817 causes

Several factors can lead to the triggering of DTC B1817, including:

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

DTC B1817 seriousness

The seriousness of DTC B1817 can vary based on the symptoms experienced. While it may not affect the vehicle’s overall drivability, it can lead to safety concerns if the rear wiper is inoperative during inclement weather. It is advisable to address this code promptly to ensure proper visibility and functionality of the rear wiper system.

How to diagnose DTC B1817

To diagnose DTC B1817, follow these steps:

1. Use an OBD-II scanner to confirm the presence of the code.
2. Inspect the wiring and connectors related to the rear wiper motor and relay for damage or corrosion.
3. Test the rear wiper motor for proper operation.
4. Check the relay for functionality using a multimeter.
5. Examine the vehicle’s control module for any faults or issues.

How to fix DTC B1817 step-by-step instructions

To fix DTC B1817, follow these step-by-step instructions:

1. Disconnect the vehicle’s battery to ensure safety.
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 replace the relay if it is not functioning correctly.
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 B1817

To erase DTC B1817, 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 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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