hey TAEK,
Your S class Left inner sensor & Left outer sensor of rear bumper is not initiated by the PTS (parktronic Sensor Unit)
possible cause
1. Check the Rear left bumper for bumps (maybe the driver hit something that cause the sensor to break or most probably "FALL OFF") this is very common
2. Check the Rear Left inner and outer sensor for loose contacts
I am sure if u have the STAR DIAGNOSIS, u will be able to read out something in ACTUAL VALUE
HOPE U ENJOY DIAGNOSIS!
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