B0106
B0106 Code Symptoms, Causes, Diagnosis & Repair Overview Guide
Quick Summary
- B0106 indicates a fault in the LIDAR Washer Actuator A circuit.
- Drivers see a washer‑system warning light and reduced LIDAR visibility in rain, snow, or mud.
- Common causes are actuator mechanical failure, wiring/connector damage, or loss of communication with the washer control module.
- Diagnosis requires a scan tool that can read ADAS modules, a visual wiring inspection, and a functional test of the actuator.
- Replacement of the washer‑actuator module or re‑programming is often the most reliable fix; Flagship One supplies VIN‑matched modules with warranty coverage.
B0106 Code: Common Symptoms, Causes, and Repair Steps
When the LIDAR Washer Actuator A fails, the windshield washer that cleans the forward‑facing LIDAR sensor stops working. The first thing most drivers notice is a dedicated washer‑system warning lamp that flashes or stays illuminated on the instrument cluster. In addition, the vehicle’s advanced driver‑assist systems (ADAS) may report “sensor obstruction” or “poor visibility” messages, and the LIDAR point cloud can appear streaked or incomplete during precipitation. Because the LIDAR sensor relies on a clear window for accurate distance measurement, the fault can degrade lane‑keeping, adaptive cruise control, and automatic emergency braking performance, especially in wet weather.
Symptoms
- Washer‑system warning light illuminated on the dash, often labeled “LIDAR Washer” or “Sensor Washer.”
- ADAS alerts such as “LIDAR obstruction,” “sensor dirty,” or reduced functionality of lane‑keep assist and adaptive cruise control.
- Streaked or missing LIDAR data displayed on the vehicle’s diagnostic screen or after‑market ADAS software.
- No spray from the LIDAR washer nozzle when the windshield‑washer lever is activated, while the conventional windshield washer still functions.
These signs appear suddenly or develop gradually as the actuator’s ability to move the LIDAR‑specific nozzle degrades.
Why This Happens
Mechanical Failure of the Actuator
The actuator is a small motor‑driven piston that pushes fluid through a dedicated nozzle aimed at the LIDAR lens. Repeated exposure to road grime, freezing temperatures, or hydraulic wear can cause the piston to seize or the motor to burn out. When the actuator cannot generate the required pressure, the washer system reports a fault and the B0106 code is stored.
Wiring or Connector Damage
The actuator is powered and controlled through a dedicated harness that runs behind the front bumper. Corrosion, chafing, or a loose connector can interrupt the 12 V supply or the PWM signal from the washer control module. Intermittent voltage drops trigger the fault detection routine, resulting in a B0106 code even if the actuator itself is functional.
Control Module Communication Fault
The LIDAR washer actuator is commanded by a body‑area control module (often integrated with the BCM or a dedicated ADAS module). If the module’s CAN‑bus transceiver develops a fault, or if the module’s firmware becomes corrupted, the command never reaches the actuator. The module then logs B0106 to indicate that it could not verify actuator operation.
Software or Calibration Error
Factory calibration aligns the actuator’s travel range with the LIDAR sensor’s field of view. A software glitch—commonly introduced after a failed flash or an improper update—can cause the module to misinterpret the actuator’s position sensor, flagging a fault despite normal hardware operation.
Diagnostic and Repair Procedures
- Retrieve the B0106 code with a scan tool capable of reading ADAS modules. Confirm that no other related codes (e.g., B0105 LIDAR Washer Actuator B) are present.
- Inspect the actuator nozzle and fluid line. Verify that fluid reaches the nozzle when the conventional washer is activated; a lack of fluid indicates a blocked line or failed pump, which should be noted but does not clear B0106.
- Perform a voltage and continuity test on the actuator power and ground wires. A healthy circuit shows 12 ± 0.5 V at the actuator connector with the washer switch engaged. Resistance between power and ground should be infinite; any low resistance suggests a short.
- Command the actuator manually via the scan tool. Most ADAS tools have an “Actuator Test” function that cycles the motor. Observe nozzle movement and listen for motor whine. No movement while voltage is present points to a mechanical failure.
- Check CAN‑bus communication. Use a bus analyzer to confirm that the washer control module transmits and receives messages on the correct IDs. Errors such as “bus off” or “error frame” indicate a module communication fault.
- Re‑flash or re‑calibrate the washer control module. If the diagnostic tool offers a “Reset Calibration” or “Update Firmware” option, apply the latest OEM software. Clear the code and retest.
- Replace the actuator if mechanical failure is confirmed. Remove the front bumper cover, disconnect the connector, and install a new actuator. Typical parts cost $120‑$250; labor is $80‑$150.
- Replace or re‑program the washer control module if communication or software errors persist. A VIN‑matched replacement unit ranges from $600‑$900, with programming labor of $200‑$300.
If the actuator and wiring pass all tests and the module still cannot command the actuator, replacement of the control module is the most reliable solution.
When Replacement Makes Sense
When repeated actuator tests reveal intermittent operation, or when the washer control module repeatedly fails communication checks after re‑flashing, the likelihood of an internal circuit board fault is high. Repairing a damaged PCB or solder joint may provide a temporary fix, but moisture ingress or thermal cycling often leads to recurring failures. In such cases, installing a new, factory‑calibrated module eliminates the root cause and restores full ADAS functionality.
Flagship One specializes in VIN‑matched control modules, providing a plug‑and‑drive solution backed by a comprehensive warranty. Modern control modules are complex and integrated with security and immobilizer systems; correct programming and compatibility are essential for reliable operation. Flagship One’s modules are pre‑programmed to your vehicle’s VIN, ensuring seamless integration and eliminating dealer‑only re‑coding delays.
Preventive Maintenance
- Clean the LIDAR washer nozzle regularly. Use a soft brush and distilled water to remove debris that can cause the actuator to work harder.
- Inspect the front‑bumper wiring harness every 12 months. Look for signs of corrosion, abrasion, or loose connectors, and reseat any questionable plugs.
- Verify washer fluid level and quality. Low fluid or contaminated fluid can clog the dedicated line, creating additional load on the actuator.
- Schedule ADAS calibration checks after major body repairs. Realignment ensures that the washer actuator’s travel limits match the sensor’s field of view.
- Avoid using high‑pressure washer jets directly on the LIDAR lens. Excessive force can dislodge the nozzle or damage the actuator linkage.
Service Recommendation: Most issues related to this fault are diagnosed and corrected through inspection, wiring repair, and calibration rather than module replacement. For modules not typically replaced through aftermarket suppliers, diagnosis and repair should be performed by a certified automotive technician with access to factory service information and tooling.