3239396 - E4020 REV COUNTER INSTRUMENT - Functional description (Q-System)

Functional description

The supply for the rev counter module E15 reaches pins 10 and 16 of connector A directly from the battery. (maxifuse J/B2 of B99 ) via fuses F2 and F3 of junction unit B1 ; this supply is used by the check device for the exterior lights. Rev counter module E15 receives a supply controlled by the ignition (INT) at pin 15 of connector A from the line protected by fuse F4 of the additional fuse box B98B . Pin 14 of connector A is earthed. The engine rpm signal, which is different for each engine type, comes from the engine management control unit M10 to pin 6 of connector B. In particular, for versions with automatic transmission, the connecting line - pin 12 of connector B of module E15 - to the gearbox management control unit M55 - pin 10 of connector A - is used for the instrument's gear indicator display and the 'automatic transmission fault' warning light. For all the other warning lights, refer to the diagrams relating to the components to which they refer.