B1816 – OBD-II DTC

OBD-II DTC B1816 – Wiper Rear Motor Down Relay Coil Circuit Short To Battery

DTC B1816 meaning

DTC B1816 refers to a diagnostic trouble code indicating a short circuit in the rear wiper motor down relay coil 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 down relay coil is receiving an unexpected voltage, it triggers this code to alert the technician of a potential electrical issue.

DTC B1816 symptoms

Common symptoms associated with DTC B1816 may include:

• Rear wiper motor not functioning
• Intermittent operation of the rear wiper
• Rear wiper motor running continuously
• Blown fuses related to the wiper system
• Dashboard warning lights illuminated

DTC B1816 causes

Several factors can lead to the occurrence of DTC B1816, including:

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

DTC B1816 seriousness

The seriousness of DTC B1816 can vary based on the symptoms and the vehicle’s overall condition. While it may not pose an immediate safety risk, a malfunctioning rear wiper can reduce visibility in adverse weather conditions, potentially leading to dangerous driving situations. It is advisable to address this code promptly to ensure proper vehicle operation.

How to diagnose DTC B1816

To diagnose DTC B1816, 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 any visible damage or corrosion.
3. Check the rear wiper motor operation by applying direct power to it.
4. Test the relay for proper function using a multimeter.
5. Examine the body control module for any faults or issues.

How to fix DTC B1816 step-by-step instructions

To fix DTC B1816, follow these step-by-step instructions:

1. Disconnect the vehicle’s battery to ensure safety while working on electrical components.
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 during testing.
4. Replace the relay if it fails the functionality test.
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 B1816

To erase DTC B1816, 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 on 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 perform a test drive to ensure the code does not reappear.

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