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Drive Position






Information about the current gear position, P-N or R-D-3-2-1, is sent from pin 11 of the transmission control module to the engine control module.

The the Motronic 5.2 receives the signal on pin 86.

When any of the gear positions R. D, 3, 2 or 1 is selected from gear position N. the transmission control module applies positive battery voltage (B+) to pin 11. Otherwise the voltage on pin 11 is 0 volts.

The intention is to inform the engine control module that a gear position (forward or.reverse) has been selected. The engine control module then ensures that engine idling speed is raised to compensate for this change in load.

Idling speed compensation is achieved by the engine control module opening the idle air control valve wider than normal so that a constant idling speed can be maintained.

In the event of no signal being received, engine idle speed will drop below 800 RPM when DRIVE is selected and then slowly rise to normal idling speed.