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Dynamic Drive: Service Function 'Commissioning'

Brief description
Commissioning is a comprehensive hydraulic system test (approx. 20 seconds), that can be used to test the interplay of all components. In advance of commissioning, the pressure sensors are also calibrated to ambient pressure (learning the sensor system) to balance out manufacturing tolerances. As a result, the commissioning indicates whether the system is OK, whether there is air in the system or whether there is a system fault.

Requirements for commissioning
The following requirements must be met before starting the commissioning of Dynamic Drive:

Check oil level in the oil reservoir
Before commissioning, the oil level in the Dynamic Drive system should be checked. With an incorrect oil level, commissioning is blocked by the control module.

Bring the engine to operating temperature
Commissioning is configured for a vehicle at operating temperature. This is why the vehicle should have reached its operating temperature before commissioning.

Learning the sensor system (with engine off)
Before starting commissioning, the values of both pressure sensors are to be learned to compensate the tolerances of the sensor zero point positions. This is executed per diagnosis command. If learning the sensor zero point positions fails, a fault is entered. This causes the control module to lock the start of commissioning.

Control module reset and clear fault memory
The next step is to run a reset and clear the fault memory of the VDM control module to eliminate any obsolete fault entries.

Engine start and pre-drive check
The engine must be started now. The increase in engine speed leads to the system running an automatic pre-drive check, as long as the system is not in a fault status. Inhibitors for a pre-drive check:
- Undervoltage
- Electrical sensor or valve faults
- Status of direction valve incorrect
- Message faults for engine speed or road speed
- Engine speed too low (< 350 rpm)

If a fault or other inhibitor is detected in the pre-drive check, the control module locks commissioning.

Speed increase
During commissioning, the same pump speed and thus the same supply volume flow of the tandem pump should be set on all vehicles of a model series. The speed increase therefore depends on the engine variant. The right engine speed for the corresponding engine variant can be read from the VDM control module. Successful adjustment of the engine speed is a precondition to be able to run proper commissioning.

Sequence for commissioning
Commissioning involves the following stations:

Start of commissioning
As soon as all the requirements for commissioning have been met, commissioning can be started with a diagnosis command. Commissioning is composed of the following four phases:
- Phase 1: Dynamic test on the front axle (high pressure test)
- Phase 2: Dynamic test on the rear axle (high pressure test)
- Phase 3: Characteristic curve test on front and rear axle
- Phase 4: Test of the intake throttle valve

Termination of commissioning
Termination of commissioning takes place under the following circumstances:
- Requirement for starting commissioning not met
- System fault detected during commissioning

A fault code is entered in both cases.

Result of commissioning
At the end of commissioning, it is automatically indicated whether a fault was detected in the hydraulic system. In order to detect the cause of the fault more exactly, the proposed test module must be run. If commissioning was completed without faults, the vehicle rolls 3 times from right to left at the end.

Notes for Service department

WARNING: Rolling motion on commissioning

During commissioning, the vehicle performs very strong and rapid rolling motions. For this reason, no persons may be located directly at the vehicle, particularly in the proximity of moving vehicle components. There must be no objects underneath the vehicle or in the wheel arches. The commissioning procedure may only be carried out with the vehicle standing of a firm, flat surface with all four wheels on the ground.

Under no circumstances may commissioning be run in the following locations:
- Lifting platforms
- Wheel alignment units
- Shock absorber test units
- Brake test units
- Power output test units

Disregarding these instructions could put lives at risk.

General information
After opening the system hydraulics, i.e. after working on the
- Valve block
- Hydraulic motors
- Lines

commissioning is to be run.

Notes on encoding / programming
After encoding or programming the control module, commissioning is to be run.