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Functional Scope Of Engine, PSM, Function - GF54.21-D-3007P

MODEL 906 with CODE ED5 (Parameterisable special module) with CODE XM0 (Facelift) Special functions 

MODEL 906 with CODE ED8 (Preinstallations electrical system, PSM) with CODE XM0 (Facelift) Special functions 

Special functions 

The PSM control unit can also influence functions in the "Engine" control unit.

For this purpose several parameterizable function modules have been implemented which ensure the correct operation of the "Engine" control unit.

IMPORTANT The control units for gasoline engines do not support PSM engine functions. In other words, vehicles with gasoline or gasoline/gas engines cannot implement the engine speed control, speed limit, external engine start and engine stop functions.

Engine speed control function 

The engine's rotational speed can be regulated through the engine speed control function.

On the one hand several fixed rpms can be specified, while, on the other hand, the rpm can also be freely adjusted using the push button switches.

For safety reasons, the working speed control function can only be used on a stationary vehicle with the parking brake applied.

Power take-off function 

The power take-off (PTO) function is used to control PTO activation on vehicles with PTO.

To prevent damage to the transmission, various conditions can be queried.

Function of speed limit 

The speed limit (GB) function is used to switch on a parameterizable speed limit.

Engine start and stop function 

The engine start and stop function enables the engine to be stopped and started using the PSM control unit.

IMPORTANT The "engine stop" and "engine start" functions are also available when the working speed control is active. It should be noted here that after an engine stop, the working speed control function is deactivated, whereupon an engine start is then no longer possible. An ignition change is necessary to reset the engine start/engine stop function.

Electric step function 

The "Electric step" function module in the PSM can be used to actuate two electric steps independent of each other.

Parameterizable options for function enable 

The software includes several options which can be used to activate and deactivate specific function modules and a number of specific functions of these function modules.

These are available in the individual functions under "Properties".

Option Description
Function "Working speed control" Activation of working speed control function module
Function "Rpm limitation without working speed control" Activation of rpm limitation function without active working speed control
"Power take-off" function Activation of PTO function module
"Activation of power take-off despite unfulfilled switch-on conditions" This triggers one of the two following requests:
  • PTO request must be the last condition that must be fulfilled to engage the PTO.
  • Request PTO does not have to be the last condition, in this case a missing condition can be skipped by pressing the power take-off switch. If this is done, an event is stored in the fault memory.
"Actuation of solenoid valve through PSM control unit" Select whether the PTO solenoid valve for the PTO is connected to the PSM control unit
Function "Speed limit" Activation of vehicle speed limit (GB) function module
Function "Engine start" Activation of engine start function module
Function "Engine stop" Activation of engine stop function module
Step 1 Activation of step 1
Step 2 Activation of step 2
Parameterizable special module (PSM) control unit component description GF54.21-D-5005P