Rain sensor

Components and Component Location

Components

Circuit Diagrams

Wiring Diagram

Description and Operation

Description

Integrated Rain Sensor

The integrated rain sensor (A) controls three systems: the front wiper, automatic lighting, and the central air conditioning.

1. Wiper Control System

   When the multifunction switch on the right receives the "AUTO" signal, the built-in rain sensor detects the amount of rainfall. The sensor is installed inside the upper part of the windshield to control the wiper motor.

   This system automatically controls the operating duration and speed of the wipers according to the measured amount of rainfall, even when the driver does not operate the wiper switch.

Functions and Operation Principles

Basic Principle

1. Rainfall Detection

   Light (beam) emitted by the LEDs is fully reflected from the outer surface of the windshield and returns to the photodiodes. If there is water on the outer surface of the windshield, the light is optically separated and partially reflected, and the remaining brightness is measured by the photodiodes. Residual water on the windshield prevents the light from being fully reflected. The loss of brightness caused by this shows how wet the glass surface is.

Interference

The rain sensor may malfunction due to the interference listed below.

1. 1

   Dust on the measuring surface and other surfaces in the beam path (surface of the LEDs and photodiodes, optical fiber, bracket, and the windshield joint surface of the glass) reduces the received light.

2. 2

   Movement of the windshield and bracket

3. 3

   Movement of the bracket due to vibration

4. 4

   Damaged wiper blade

Automatic Operation

1. Rain Sensor Operating Condition

   Operation Mode	Operation
   Direct Mode	This is the basic operating condition when the rain sensor detects a dry windshield with the wiper switch in the "AUTO" position. In this mode, the built-in rain sensor determines the wiper operation according to the amount and duration of rainfall.
   Intermittent Mode	The built-in rain sensor activates intermittent mode when the wiper operates more than two times in succession with a pause of 0.5 - 5 seconds.
   Low speed	Wipers operate continuously at low speed
   High speed	Wipers operate continuously at high speed

Safety Function

1. When ice or foreign material is present in the detection area, the integrated rain sensor cannot correctly recognize the operating conditions.

Special Condition Detection

1. Rain sensor

   Special Condition	Operation Based on Special Condition Detection
   Hesitation	When the built-in rain sensor detects a high level of water (spray) in direct or intermittent mode, the system switches from park mode to high speed. Then wiping is performed once at high speed and once more at low speed. If the precipitation condition does not change after wiping, it returns to the original state (direct or intermittent).
   Smearing	Smearing is a thin oil film that dries quickly and occurs when a small amount of precipitation is wiped by a dirty or worn wiper blade. The operating signal should not be output when smearing occurs in direct or intermittent mode.
   Mud	If no change is detected after wiping, the built-in rain sensor determines that the windshield is contaminated. In this condition, the operating signal should not be output. If the windshield becomes clean (for example, by washer fluid), the built-in rain sensor returns to normal.
   Washer Fluid	The built-in rain sensor does not respond to washer fluid during washing mode. In other words, the wiping speed does not change even if washer fluid is sprayed (automatic operation of the washer pump does not affect the operation of the built-in rain sensor).

Repair Procedures

Removal

1. 1

   Remove the mirror wiring cover (A).

   

   

2. 2

   Disconnect the rain sensor connector (A).

   

3. 3

   Be careful not to damage the cover latch by applying excessive force. To release the latch, pull the latch to the side using the hole in the cover with a small flat-tip screwdriver (A).

   1. Insert a small flat-tip screwdriver (-) into the hole at the bottom or top, between the rain sensor and the bracket.

   2. Slowly pull the rain sensor up and down in the vertical direction of the glass, then slowly remove the rain sensor from the windshield without damaging the silicone on the sensor.

   

   

4. 4

   The rain sensor module is attached to the windshield with adhesive. When replacing the windshield, remove the rain sensor module from the existing windshield and install it on the new windshield.

Installation

1. 1

   Connect the rain sensor connector.

2. 2

   Press down one of the spring arm latches (A) until it clicks into place and you hear a click.

   Then press the latch of the second spring arm (B) to hold the sensor in the correct position.

   

Replacement

Gel Pad

1. 1

   Completely remove the damaged silicone gel pad from the rain sensor lens plate.

   

2. 2

   Remove the two protective films (A) from the gel pad.

   

3. 3

   Manually attach the silicone gel pad (A) to the rain sensor lens.