Rain sensor on ŠKODA Yeti: device, diagnostics and DIY replacement

Rain sensor on ŠKODA Yeti is a small but extremely important device that automatically turns on the windshield wipers at the first drop of rain. The system not only adds comfort to the driver, but also improves safety, allowing you to concentrate on the road in difficult weather conditions. However, like any electronic component, the sensor can fail, which leads to incorrect operation of the wipers or complete system failure.

In this article we will look in detail at how the rain sensor works on Yeti, what signs indicate its malfunction, and how to independently diagnose or replace it. We will pay special attention to models with the system Climatronic and cars after facelift in 2014, where the sensor design was changed. You will also find connection diagrams, calibration recommendations and answers to frequently asked questions from owners.

How does the rain sensor work on the ŠKODA Yeti

Rain sensor in ŠKODA Yeti integrated into the upper part of the windshield, next to the rear view mirror. It works on the principle infrared reflection: There is an LED inside the device that sends a beam to the glass at a certain angle. If water drops appear on the surface of the glass, they change the angle of reflection, and the photodiode records this change. Based on the data received, the electronic control unit (ECU) activates the windshield wipers with a given intensity.

The system is closely connected with other vehicle sensors:

• 🌡️ Ambient temperature sensor — prevents false alarms when the glass fogs up.
• 🚗 Speed sensor — adjusts sensitivity depending on movement (at high speed the wipers turn on faster).
• 🔦 Light sensor — in some trim levels it synchronizes the operation of the wipers with the inclusion of headlights.

On models Yeti Until 2014, the rain sensor was often combined with a light sensor (RLS — Rain/Light Sensor), and after facelift these functions can be separated. It is important to take this into account when selecting spare parts.

Signs of a faulty rain sensor

A faulty rain sensor manifests itself in different ways, but the most common symptoms are:

• 🚨 The wipers turn on spontaneously without rain (false alarms).
• ☔ Wipers don't react for real rain or trigger with a long delay.
• ⚡ Lights up on the dashboard ESP error or ABS (the rain sensor is connected to the on-board network via CAN bus).
• 🔧 Errors like this appear in the diagnostic scanner: B105A00 (rain/light sensor malfunction).

Sometimes the problem lies not in the sensor itself, but in dirty glass or damaged wiring. For example, if the glass is tinted with a metallic layer, this may block the infrared signal. False alarms also occur when direct sunlight hits the sensor or when the glass is heavily fogged.

⚠️ Attention: If after washing the car the wipers begin to work randomly, check to see if water has entered the sensor connector. This is a common cause of temporary failures.

Symptom	Possible reason	Solution
Wipers do not turn on when it rains	Sensor or glass dirty	Clean the glass with alcohol, check the transparency of the sensor area
Spontaneous activation of the wipers	Moisture in the connector or damage to the wiring	Dry the connector, check the circuit with a multimeter
Error B105A00 in diagnostics	Sensor malfunction or open circuit	Replacing the sensor or repairing the wiring
The wipers work jerkily	Incorrect calibration or software failure	Reset settings via VCDS or ODB11

Diagnostics of the rain sensor on the ŠKODA Yeti

Before you start replacing the sensor, you need to check its functionality. To do this you will need a multimeter and access to the diagnostic connector. OBD-II.

Step 1. Visual inspection

• 🔍 Check the integrity of the glass in the sensor area (cracks or chips may distort the signal).
• 🧴 Make sure there are no greasy stains or cleaning residues on the glass (they can cause optical interference).
• 🔌 Inspect the sensor connector for oxidation or corrosion.

Step 2: Check the voltage

Disconnect the sensor connector and measure the voltage at the contacts with the ignition on:

• Pin 1 (power) - must be 12 V.
• Contact 2 (ground) — 0 V (check the integrity of the mass).
• Pin 3 (signal) — the voltage should change when water hits the glass.

Step 3: Test with a diagnostic scanner

Connect the scanner (VCDS, OBDeleven or Carista) and check the block 09 — Cent. Elect. for errors. If the error B105A00 appears again after reset, the sensor is faulty.

⚠️ Attention: On models Yeti with the system KESSY (keyless entry) The rain sensor can be connected to the comfort unit. When replacing it, adaptation through diagnostic equipment may be required.

Replacing the rain sensor on a ŠKODA Yeti: step-by-step instructions

If diagnostics confirm that the sensor is faulty, it must be replaced. For this you will need:

• 🔧 Flathead screwdriver or plastic pick.
• 🔨 New sensor (original number - 5E0 955 559 B for models up to 2014, 5Q0 955 559 A for restyled ones).
• 🧴 Alcohol for cleaning glass.

Step 1. Removing the old sensor

1. Disconnect the negative terminal of the battery.
2. Carefully pry the sensor from the side with a flat-head screwdriver (it is attached with double-sided tape).
3. Disconnect the connector by pressing the latch.

Step 2: Preparing the New Sensor

Clean the installation area on the glass with alcohol. Do not use acetone or solvents - they may damage the optical elements of the sensor. Make sure there are no scratches or glue residue on the glass.

Step 3: Installation and Calibration

1. Remove the protective film from the new sensor and glue it in place of the old one.
2. Connect the connector (you should hear a click from the latch).
3. Connect the battery and perform calibration using the diagnostic scanner (in the 09 — Cent. Elect. select Adaptation → Rain Sensor).

Setting the sensitivity of the rain sensor

The sensitivity of the sensor can be adjusted through the on-board computer menu or diagnostic equipment. On ŠKODA Yeti 4 sensitivity levels available:

• 🌧️ Level 1 — minimal sensitivity (the wipers turn on only in heavy rain).
• 🌧️🌧️ Level 2 — standard mode (recommended for most conditions).
• 🌧️🌧️🌧️ Level 3 — high sensitivity (useful in drizzle or fogging).
• 🌧️🌧️🌧️🌧️ Level 4 — maximum sensitivity (can be triggered by splashes from oncoming cars).

To change settings:

1. Turn on the ignition.
2. Press and hold the button SET/RESET on the steering column switch.
3. Scroll to Rain sensor and select the desired level.

If there is no menu, setting can be done via VCDS:

Adaptation → Block 09 → Channel 12 → Enter a value from 1 to 4

⚠️ Attention: If the sensitivity is too high, the sensor may react to dirt or insects on the glass. Optimal mode - level 2.

Common replacement mistakes and how to avoid them

Many owners ŠKODA Yeti encounter problems after replacing the sensor themselves. Let's look at typical mistakes:

• 🔄 Poor polarity When the connector is connected, the sensor fails.
• 🧴 Using the wrong glue — the sensor will fall off in a few days.
• 🔧 Skip calibration — the wipers work jerkily or do not respond to rain.
• 🚗 Ignoring errors in other blocks (for example, in ABS), which may affect the operation of the sensor.

On restyled models Yeti (after 2014) a rain sensor can be combined with a rear view camera. When replacing it, additional adjustment of the camera viewing angle is required via VCDS.

What should I do if, after replacing the sensor, the wipers work constantly?

This indicates a short in the signal wire circuit. Check the sensor connector for short circuit or damaged insulation. If the problem persists, the control unit may be faulty BCM (Body Control Module).

Alternative solutions: repair vs replacement

In some cases, the rain sensor can be repaired without having to completely replace it. Let's consider the options:

1. Cleaning the optics

If the sensor is dirty from the inside, you can disassemble it and clean the lenses with alcohol. To do this:

1. Carefully separate the sensor housing (usually it is glued together).
2. Clean the inner lenses with a cotton swab dipped in alcohol.
3. Reassemble the sensor and check operation.

2. Connector repair

Oxidized contacts in the connector can be restored:

• Disconnect the connector and clean the contacts with sandpaper (grain 600-800).
• Apply a special grease for electrical contacts (for example, Liqui Moly Electronic-Spray).

3. Replacing glass with sensor

If the glass is cracked in the sensor area, it will have to be replaced along with the sensor. In this case it is recommended:

• Order glass with a pre-installed sensor (for example, from Pilkington or Saint-Gobain).
• Check with your installer to see if additional calibration is required after replacement.

Problem	Repair	Cost (RUB)
Optics contamination	Cleaning with alcohol	0 (on your own)
Connector oxidation	Cleaning contacts	0–300 (lubrication)
Crack in glass	Replacing glass with sensor	15 000–25 000
Sensor malfunction	Replacement with a new one	3 000–8 000

FAQ: Frequently asked questions about the rain sensor on the ŠKODA Yeti

Is it possible to drive without a rain sensor?

Yes, the car will remain driving, but the wipers will have to be turned on manually. However, in the block BCM An error may persist and light up every time the engine is started. On some models, this also disables the auto light feature.

Which rain sensor fits the 2015 Yeti?

For restyled models (after 2014), the original sensor number is 5Q0 955 559 A. Analogues: HELLA 8XL 355 043-551 or VALEO 698253. Make sure the sensor is compatible with your system Climatronic (if installed).

Why does the rain sensor work at night?

This is due to the fact that the infrared signal may be reflected from the headlights of oncoming cars or street lights. Try reducing the sensitivity of the sensor or check if moisture has gotten under the glass (for example, after washing).

Is it possible to turn off the rain sensor?

Yes, this can be done through diagnostic equipment (VCDS → Block 09 → Coding → disable the bit responsible for the rain sensor). However, after this, the automatic wiper function will not be available.

How much does it cost to replace a rain sensor at a service center?

The cost of working in the service is 1,500–3,000 rubles (excluding the cost of the sensor). If calibration via a scanner is required, the price may increase by 500–1,000 rubles.