General Information

Front Area Module
B1907 Rain Sensor Fault 3 - General Information

Component Location





General Description

FAM controls low/high relay of wiper according to rain sensor signal when a wiper auto switch is turned to ON under IG ON.
As wiper INT switch is set at AUTO mode, combination switch transmits value of INT step to ECW by LIN communication. And, ECW communicates with FAM by CAN.
[FAM output signal (FAM -> Rain sensor)]
FAM transmits sensitivity step signal from INT switch to the rain sensor by pulse signal.




[FAM input signal (Rain sensor -> FAM)]
The Rain sensor transmits moisture status and the desired wiper speed to FAM by pulse signal.




* The Rain sensor has various outputs according to each modes as below. (Duty cycle changes)
Rain sensor output signal (Rain sensor -> FAM)






DTC Description

FAM outputs this code when FAM can't receive data from the rain sensor.
1. In case of shaking the rain sensor after detaching from windshield.
2. In case each circuits of input and output are shorted to ground.
3. In case each circuits of input and output are shorted to power.
4. In case each circuits of input and output are open.
5. In case the rain sensor connector is disconnected.

DTC Detecting Condition





Diagnostic Circuit Diagram





Signal Waveform & Data
































Fig.1) Signal waveform at Wiper AUTO Switch "AUTO OFF"-Rain Sensor Input_Output Signal
Fig.2) Signal waveform at Wiper AUTO Switch "AUTO ON-LOW"-Rain Sensor Input_Output Signal
Fig.3) Signal waveform at Wiper AUTO Switch ON-INT "Auto Fast"-Rain Sensor Input_Output Signal
Fig.4) Signal waveform at Wiper AUTO Switch ON-INT "Auto Low-a drizzling rain"-Rain Sensor Input_Output Signal
Fig.5) Signal waveform at Wiper AUTO Switch ON-INT "Auto Low-heavy rain"-Rain Sensor Input_Output Signal
Fig.6) Signal waveform at Wiper AUTO Switch ON-INT "Auto Fast-a drizzling rain"-Rain Sensor Input_Output Signal
Fig.7) Signal waveform at Wiper AUTO Switch ON-INT "Auto Fast-heavy rain"-Rain Sensor Input_Output Signal
Fig.8) "Wiper State" & "Rain Sensor Output" (With wiper switch "AUTO" & engine running)