9-3 Viggen Coupe (9400) L4-2.3L Turbo (B235) HO (1999)
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Transmission Position Switch/Sensor: Description and Operation
Drive Position
Drive Position
Information on the current gear position, P-N or R-D-3-2-1,is sent from the transmission control module pin 11 to the engine control module.
Motronic receives the signal on pin 47 and Trionic on pin 14.
When shifting from N to any of the gear positions R, D, 3, 2 or 1, the transmission control module put B+ on pin 11. Otherwise the voltage is 0 V. This
is to inform the engine control module that a gear position (forward or reverse) has been selected. The engine control module then ensures that the idling
speed is compensated for the change in load.
Idle speed compensation is achieved by the engine control module opening the idle air control valve more than normal, whereby retaining a constant
idling speed. If the signal is absent, the idling speed will drop below 900 rpm when DRIVE is selected and then slowly increase to normal idling speed.
