GF28.19-P-3500VG Component Description of Rear Axle Differential Lock Control Unit

GF28.19-P-3500VG Component description of rear axle differential lock control unit
- with engine 156, 272, 273, 642 [model 164.1]
- with engine 273, 642 [model 164.8]
- Transmission 722.9
- with CODE (430) Offroad package

Component Identification:

Location
The rear axle differential lock control unit is located on the trunk floor on the left in the direction of travel.

Task

General
The rear axle differential lock control unit is responsible for actuating the multidisk clutch (interwheel differential lock) in the rear axle differential in order to guarantee the distribution of the engine torque between the left and right rear wheels.

The following control functions are performed by the rear axle differential lock control unit:
- Torque interface
- Compensation process
- Lock protection function
- Plausibility monitoring
- Diagnosis
- Flash programming
- Run-on function

CAN data bus
The rear axle differential lock control unit is connected to the CAN system of the vehicle via the engine compartment CAN (CAN-C).

Input and output signals
The rear axle differential lock control unit evaluates the following input signals and issues the corresponding output signals:
^ Direct input signals
^ Direct output signals
^ CAN input signals
^ CAN output signals

Direct input signals
- Circuit 15
- Circuit 30
- Circuit 31
- Hall sensor 1 signal - Rear axle differential actuator motor (M70)
- Hall sensor 2 signal - Rear axle differential actuator motor
- Motor temperature - Rear axle differential actuator motor

Direct output signals
- Sensor supply (5V)
- Hall sensor 1 and 2 sensor ground - Rear axle differential actuator motor
- Temperature sensor ground - Rear axle differential actuator motor
- Actuator motor actuation - Rear axle differential actuator motor
- Engine brake actuation - Rear axle differential actuator motor

CAN input signals
Central gateway control unit (N93)
- Diagnosis request

Transfer case control unit (N15/7)
- Specified locking torque

CAN output signals
Central gateway control unit (N93)
- Diagnostic data

Transfer cap control unit (N15/7)
- Actual value of rear differential lock