Rain Sensor: Testing and Inspection

RAIN SENSOR





Description
Rain sensor judges a wiping speed for front wiper by rain condition and the vehicle conditions. And it transmits the wiping speed request signal to the BCM via the rain sensor serial link.




Component Function Check
1.CHECK FRONT WIPER AUTO OPERATION
1. Clean rain sensor detection area of windshield fully.
2. When the front wiper switch is turned to INT position, front wiper operates once regardless of a rainy condition.
Is front wiper (AUTO) operation normally?
YES - Rain sensor circuit is normal.
NO - SEE Diagnosis Procedure.




Diagnosis Procedure
1.CHECK RAIN SENSOR FUSE
1. Turn the ignition switch OFF.
2. Check that the rain sensor 10 A fuse (#6) is not fusing.
Is the fuse fusing?
YES - Replace the fuse after repairing the applicable circuit.
NO - GO TO 2.
2.CHECK RAIN SENSOR POWER SUPPLY
1. Disconnect rain sensor connector.
2. Check voltage between rain sensor harness connector and ground.





Is the measurement value normal?
YES - GO TO 3.
NO - Repair or replace harness.
3.CHECK RAIN SENSOR GROUND CIRCUIT
Check continuity between rain sensor harness connector and ground.





Does continuity exist?
YES - GO TO 4.
NO - Repair or replace harness.
4.CHECK RAIN SENSOR SIGNAL
1. Connect rain sensor connector.
2. Turn ignition switch ON.
3. Check signal between BCM harness connector and ground with oscilloscope.






Is the measurement value normal?
YES - Replace rain sensor.
NO - GO TO 5.
5.CHECK RAIN SENSOR SIGNAL CIRCUIT FOR OPEN
1. Disconnect BCM connector and rain sensor connector.
2. Check continuity between BCM harness connector and rain sensor harness connector.





Does continuity exist?
YES - GO TO 6.
NO - Repair or replace harness.
6.CHECK RAIN SENSOR SIGNAL CIRCUIT FOR SHORT
Check continuity between BCM harness connector and ground.





Does continuity exist?
YES - Repair or replace harness.
NO - Replace BCM. Exploded View.