Self-diagnosis function (Peugeot Eurovans 806)

The Bosch Motronic MP3.2 system has a self-testing capability, which consists of continuously evaluating signals received from sensors and, if a malfunction is detected, entering a corresponding code into a specially allocated memory. An appropriate fault code reader (FCR) can retrieve this code from the Bosch Motronic serial port (see illustrations 11.7, 11.8). If the electronic control module (ECM) detects a malfunction, it grounds pin #2, and the malfunction indicator lamp (MIL) illuminates on the instrument cluster. The lamp remains illuminated until the malfunction is corrected. If a fault is detected, the code will remain stored until it is cleared from the memory with an appropriate fault code reader or the battery is disconnected. The electronic control unit is a valuable auxiliary device for troubleshooting. A number of faults are classified as minor, and when detected, the control lamp does not light.







In addition to the self-test function, the Bosch Motronic MP3.2 has a special device (LOS mode, allowing you to get to the nearest workshop). If a major fault occurs in one or more sensors, the electronic engine management system will detect a fault in place of the faulty sensor. This means the engine may run reasonably well if the fault is in one or more auxiliary sensors. If a major sensor, such as the Manifold Absolute Pressure (MAP) sensor, is damaged, the vehicle's handling performance will be reduced.

Note: Most models are equipped with a standard 2-pin PSA multi-plug connector. Later models (for example, X. ntia) equipped with a new 2-pin self-diagnostic connector (SD).