Due to tolerances when manufacturing the unit pumps the injected fuel quantity may deviate between the actual and calculated fuel quantity. After manufacture these deviations are determined for every unit pump and a calibration value is determined, the value is converted to a code that is stamped on the unit pumps. This code is programmed in the engine control unit for each cylinder. Using these codes, the engine control unit corrects the calculated fuel quantity individually for each cylinder and thus improves engine operation and exhaust emissions. With this function, new calibration values can be entered in the engine control unit when replacing unit pump.
Read off the number on the unit pump and enter it as in the following example: 8355
Note:
Incorrect entry may lead to rough engine operation and overloading of individual cylinders.
Test conditions:
Parking brake applied.
Ignition on, engine off.
Battery voltage above 24V.
Procedure:
Start the function.
A dialogue box shows test conditions, check these and press "OK".
Follow the instructions in the program.
If the function fails, check the test conditions and repair any faults.