Open Road Cruise Control Function

Open Road Cruise Control Function

General Information, Components

The following components are needed in order to have Open Road Cruise Control Function.

• Distance Regulation Control Module (J428)

• Engine Control Module (J623)

• Cruise Control Switch (E45)

• Instrument Cluster Control Module (J285)

• ABS Control Module (J104)

• ABS Wheel Speed Sensors (G44, G45, G46, G47)

Function Description

The driver activates the control and accelerates until the specified speed is reached, then pushed the SET button on the cruise control switch.

The ABS control module calculates the number of pulses from the speed sensors and sends this information to the instrument cluster/chassis CAN.

The instrument cluster control module needs to know the number of pulses in order to calculate the speed.

The distance regulation control module reads the speed signal, which the instrument cluster control module has sent to the chassis CAN. From that it calculates the acceleration necessary to maintain the previously set speed, and then sends this information to the engine control module.

Should the actual speed be different from the specified speed, the distance regulation control module will recognize this difference and will send a newly calculated specified acceleration to the engine control module.

The engine control module determines if it should increase or decrease the amount of fuel injected in order reach the specified acceleration or if it should activate the brakes (performed by the ABS control module).

Service Information

If the engine control module was replaced, then the cruise control system must be coded using a Vehicle Diagnostic Tester in "Guided Functions".