Due to tolerances when manufacturing the injectors the injected fuel quantity may deviate between the actual and calculated fuel quantity. After manufacture these deviations are determined for every injector and a calibration value is determined, the value is converted to a 7-character code that is stamped on the injectors. 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 injectors or engine control unit.
When replacing one or more injectors these shall be adapted to the engine control unit.
When replacing engine control unit, all injectors shall be adapted to the new control unit.
The 7-character code is stamped on the injectors and may include both letters and numbers, see figure.
Test conditions:
Ignition on, engine off.
No faults in the system.
Procedure:
Select the function "Injector programming", press "OK".
Select the cylinder to be adapted, press "OK".
The existing code for the selected cylinder is shown. If the code is to be changed, press "YES", otherwise "NO" to cancel the function.
A dialogue box is shown. Enter the 7-character code, press "OK" to perform the adaptation.
If the adaptation is successful the new stored code is shown for the cylinder in question.
If "operation failed" is shown, check the code.
If additional cylinders are to be adapted, press "YES" to select a new cylinder, if no other cylinders are to be adapted press "NO" to exit the function.
After finished function, finish communication with car, turn off the ignition for 30 seconds, turn on the ignition, re-establish communication with car, and check that no fault codes are stored.