The test module for the engine test runs automatically in a defined order after connecting the test leads. In the process, it checks all engine-specific systems fitted in the vehicle.
All the results are displayed at the end of the test module. They can then be printed out via the diagnostic record.
All operating values must be read out and compared with nominal values. They are then assessed with the three criteria ”OK”, ”Not OK” and ”In the limit range”.
”In the limit range” means that although the value was OK it lies close to the limit of ”Not OK”.
The camshaft position and pulse duty factor of cylinder banks 1 and 2 are queried and compared with nominal values.
The system checks are used to determine the adjustment rate and leak-tightness of cylinder banks 1 and 2.
The primary-side ignition signal for cylinders 1 to 8 is picked up at the adapter box of the digital engine electronics control unit and then automatically evaluated.
The activation signals for the fuel injectors for cylinders 1 to 8 are picked up at the adapter box and then automatically evaluated.
The tank-ventilation system is checked with the system check.
After the check with the system check secondary air system, the fault code memory of the secondary air system of cylinder banks 1 and 2 is read out.
For US vehicles of model series E38 and E39 up to 09/2000, the leak-tightness of the fuel tank is checked with the system check for the tank-leak diagnosis LDP.
For US vehicles of model series E53 and E39 up to 09/2000, the leak-tightness of the fuel tank is checked with the system check for the tank-leak diagnosis DMTL.
On cars with automatic transmissions, the fault memory of the transmission control unit is read out. If a fault is stored, the transmission management system is evaluated as ”Not OK”.
The relative compression test is only carried out if the irregular running measurement is not OK and at the same time the signals of the ignition and fuel injection are OK.
The results are now displayed on the screen. There is then the possibility to print them in the form of a diagnosis report.