Park assist systems come in many variations. These are part of what is now known as ADAS (Advanced Driver-Assistance Systems). Park assist systems rely on various sensors to help you avoid objects while parking your car. Follow this Real Fix to see how a problem with the parking assistance system on a BMW 530xi was diagnosed and repaired.
Vehicle
2007 BMW 530xi 3.0L
Title
Code 9E39, Replaced Park Assist Sensor
Complaint
The customer states the park assist light is on.
Cause
Connected a scan tool and found code 9E39 – Lines, Front Center Left, Ultrasonic Sensor. With the vehicle in reverse, monitored live scan tool data and observed the park assist sensor parameter was erratic. Inspected the park assist sensor wiring harness and connector, but detected no obvious faults. With the ignition on and the engine off, used a multi-meter to check for the presence of voltage and ground at the park assist sensor connector and found both were present. Removed the park assist sensor and a visual inspection revealed the sensor was damaged.
Correction
Replaced the park assist sensor. Cleared the codes and performed a road test to verify the vehicle operated properly.