General Information

Instrument Panel Module (PIC+)

B1978 Electric Steering Column Lock Failure - General Information

Component Location





General Description

All 13 units which consists of the Body Electrical Control System are linked by CAN* line.
They are IPM (Inter Panel Module), FAM (Front Area Module), PDM (Power Distribution Module), DDM (Drive Door Module), ADM (Assist Door Module), ECW (Electronic Control Wiper), CLU (Cluster), MFSW (Multi Function Switch), PSM (Power Seat Module), SCM (Steering Control Module), PTM (Power Trunk Lid Module), FBWS (Front Back Warning System), DATC (Dual Auto Temperature Control Module).
The steering wheel's Lock/Unlock state from ESCL (Electronic Steering Column Lock) and the related data to starting from EMS are sent to IPM by the serial communication line.
* CAN (Controller Area Network): CAN is serial bus communication type which links not only communication system but also control units each other.
*2 LIN (Local Interconnect Network): LIN is serial communication type which is used in electrical control system. (This is less expensive.)






DTC Description

This code is outputted when ESCL cannot lock or unlock the steering wheel normally.
(When ESCL Lock/Unlock switch state from PDM to IPM is different from the switch state from ESCL to IPM.)

DTC Detecting Condition





Diagnostic Circuit Diagram





Signal Waveform & Data








Fig.1) ESCL Data Signal Waveform (UNLOCK STATE)
Fig.2) ESCL Data Signal Waveform (LOCK STATE)