Steering Column Electronic Module CIM - Function Opel Vectra C

Block Diagram

CAN abbreviations

Block Diagram (Continued)

Function Table

Functional Description

CIM Control Unit

The CIM control unit is the central control unit for the low-speed bus system. It is also the interface between low-speed CAN bus and high-speed CAN bus.

See also Chapter: CIM interface – function

Voltage Management, Voltage Supply, Ignition Lock

See also Chapter: Voltage management and transport mode (logistic mode)

Diagnosis Interface

The CIM provides a CAN diagnosis interface to the HSCAN and LSCAN. In order to prevent damage to the control units in the CAN system due to external voltage or ground connections, the CIM is provided with an internal protection circuit for both the HSCAN as well as the LSCAN.

Dimming for Steering Wheel Remote Control

The steering wheel remote control buttons are illuminated. The illumination dimming is effected by information, which is transmitted from the BCM to the CIM via the CAN.

Turn Signal Function

The CIM registers 4 switch positions of the turn signal lever in digital form. This information is transmitted from the CIM to the BCM via the CAN bus.

Cruise Control Function

The CIM registers the 3 switch positions of the cruise control This information is transmitted from the CIM to the ECM via the CAN.

Screen Wiper Function

The CIM registers 6 positions (2 upwards, 2 downwards, forwards and backwards) of the screen wiper lever. This information is transmitted from the CIM to the UEC via the CAN. In order to ensure screen wiper function, even in the event of failure of the CIM or a non-functional data communication via CAN, an additional wire provides for actuation of the screen wipers in speed stage 2.

Horn Function

The CIM registers the switch position for the horn. This information is transmitted from the CIM to the UEC via the CAN.

Immobiliser Function

See also Chapter: Immobiliser – function

Loudspeaker Function

Following a request from the CIM, UEC, BCM, DSM, IPC, DIS or PAS control unit via CAN, the CIM triggers an acoustic signal via the integral loudspeaker. There is a specific signal for each function. For example, the BCM control unit transmits a message to the CIM, which specifies the frequency of the acoustic signal (normal turn signal frequency or increased turn signal frequency in the case of a defective turn signal lamp). Furthermore, an integral volume adaptation is applied, depending upon ambient noise levels. Further acoustic signal functions of the CIM are parking light activation, open door / luggage compartment / tailgate, park pilot, screen wiper switch-off and deactivation of transport mode.

Steering Wheel Remote Control Function

The CIM registers the actuated button of the steering wheel remote control and, in the case of multiple actuations, the button with the highest priority is always evaluated. This information is transmitted from the CIM to the DIS via the CAN. A part of this information is then transmitted to the radio via the DIS interface.

Info Display Function

The CIM registers actuation of the info display operating button. This information is transmitted from the CIM to the DIS via the CAN. A part of this information is then transmitted from the CIM to the radio control unit via the DIS interface.

Steering Angle Registration Function

The CIM is either provided with a Hall sensor or a steering angle sensor. This sensor registers the current steering angle or the current steering movement and transmits this information to the CIM control unit. The steering angle / Hall sensor signal is used internally in the CIM for turn signal resetting. The steering angle is transmitted from the CIM to the ABS/ESP control unit via the CAN. The EHPS also uses this information.

Airbag Ignition Signal

The airbag ignition circuit is looped through to the driver's airbag via the CIM contact units.

Key Remote Control Function

The CIM is provided with a receiver, which implements the radio remote control signal. The CIM evaluates this information and transmits it to the BCM via the CAN in order to activate the central door locking function.

High/low Beam Function

The CIM registers the 2 switch positions of the high/low beam switch. This information is transmitted from the CIM to the UEC via the CAN.

Key Enabling Function

The key enabling function is only active in vehicles with automatic transmission. The SLM transmits the current selector lever position to the CIM via the CAN. If the current selector lever position is "P", the key lock is deactivated by the CIM and the ignition key can be removed.

Starter Check Function (Terminal Control)

If the CIM recognises the "Start engine" ignition key position, it transmits a CAN message to the ECM in order to actuate the starter.