General Information

Front Area Module
B1905 Rain Sensor Fault 1 - General Information

Component Location





General Description

FAM controls the low/high wiper relay according to rain sensor signal when the wiper auto switch is turned to ON under IG ON.

NOTE :
The rain sensor is mounted on the interior side of the front windshield glass behind the rearview mirror. If driver turns the wiper switch to AUTO, this signal is inputted to FAM by LIN communication.
FAM transmits 5 steps of signals (Slow <-> Fast) from the wiper auto switch to the rain sensor.
At the slowest step among the INT switch, the rain sensor becomes the most insensitive status.
At the fastest step among the INT switch, the rain sensor becomes the most sensitive status to measure the amount of rain.
So, the sensitivity of the rain sensor depends on the steps of the INT switch.
The rain sensor transmits the desired speed of a wiper by duty signal to FAM.





[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 it detects internal error of rain sensor after wiper switch has been turned to AUTO under IG "ON" or IG "ON" & ENG "ON".

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)