Self-test, function

Self-test

The Parktronic control unit (N62) carries out a self-test immediately after the ignition is switched on, all 16 LEDs of the center instrument panel PTS warning indicator (A44/4) and rear PTS warning indicator (A44/3) are actuated for approx. 1 second.

If no system errors or obstacles are detected, the first LED of each display lights up dimly indicating that the system is operational. If the system is operating correctly, it automatically switches to the measuring mode and displays the current measured value. The Parktronic control unit(N62) conducts other tests at regular intervals.

The Parktronic control unit (N62) monitors the front bumper PTS sensor unit (A42), the rear bumper PTS sensor unit (A43) and the wiring. Faults found are stored, the center instrument panel PTS warning indicator (A44/4) and rear PTS warning indicator (A44/3) are also diagnosed. Via the bidirectional interface between the Parktronic control unit (N62) and center instrument panel PTS warning indicator (A44/4) and the rear PTS warning indicator (A44/3) is it possible to report back faults occurring in the

center instrument panel PTS warning indicator (A44/4) and rear PTS warning indicator (A44/3) (LED inoperative, piezo-sounder defective) to the Parktronic control unit (N62).

A fault can also be caused by an externally generated ultrasound signal (compressed air). In each case 2 red LEDs are displayed in the center instrument panel PTS warning indicator (A44/4) and rear PTS warning indicator (A44/3) are displayed in each case, there is no acoustic warning. If there is also a fault during the sensor check while driving (18 to 40 km/h), the event will be interpreted as a fault and additionally a chime output the next time the upper limit speed (16 km/h) is not reached, the display goes out after a further 20 seconds. Definite faults are signaled immediately by 2 red LEDs and a chime.

The display extinguishes after 20 seconds. All errors are stored in the diagnostic trouble code memory.