DTC B1850: Driver Lumbar Horizontal Sensor Circuit Malfunction: Description

Lumbar horizontal position sensor receives 5-volt reference and ground from Memory Seat Module (MSM). Lumbar horizontal position sensor also has a signal circuit that is wired to MSM. Lumbar horizontal position sensor sends a voltage signal that varies with movement of seat through signal circuit to MSM. Then based on this voltage signal, MSM determines position of the seat.

DTC B1850 will set if MSM sees input from sensor as either less than 0.25 volt or greater than 4.75 volts. DTC B1850 will not set if B1327 is set as current. When DTC is set, MSM disables memory recall and easy exit/entry action commands of motor monitored by sensor. Motor will respond to manual positioning commands only.

DTC B1850 will clear when MSM sees input from sensor between 0.25-4.75 volts during one cycle of checking MSM inputs.