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Throttle body actuator (604), E39

Throttle body actuator (604), E39

Location

The actuator is integrated in the actual throttle body. Throttle body actuator (604), E39 .

Main task

Throttle control converts the value of the airmass control to a requested voltage for throttle position sensor 1 (P1) and compares this with the current value of the sensor.

The difference gives rise to a throttle motor PWM with a polarity that turns the throttle until the current value agrees with that requested. The PWM ratio increases the further from its nominal value the throttle is.

The ECM, E39 (590), checks that the actual airmass/combustion matches that requested. If necessary, throttle position is fine-tuned.


Type

The throttle position sensor is potentiometer type with brushless throttle motor.

Connection

604 pin no. Signal type Description
A Control (PWM) Throttle motor, connection to ECM, pin 16(B).
B Control (PWM) Throttle motor, connection to ECM, pin 32(B).
C Ground Ground for throttle position sensors 1 and 2 (P1 and P2), from ECM, pin 54(B).
D Signal. Voltage increases with the throttle position. Signal from throttle position sensor 1 (P1), connected to ECM, pin 33(B).
E Power supply, 5 V Power supply from ECM, pin 34(B), to throttle position sensors 1 and 2 (P1 and P2).
F Signal. Voltage decreases with the throttle position. Signal from throttle position sensor 2 (P2), connected to ECM, pin 35(B).



The throttle valve in the throttle body is rotated by a brushless throttle motor powered from EDM, pins 16(B) and 32(B), with a 600 Hz PWM.

The control module can order throttle rotation in both directions by reversing the polarity of the motor.

Two throttle position sensors, P1 and P2, are connected to the throttle spindle. The sensors comprise potentiometers powered with 5 V from ECM pin 34(B) and are grounded through ECM pin 54(B).

The signal from throttle position sensor 1 (P1) is connected to ECM pin 33(B) and increases with the throttle position.

The signal from throttle position sensor 2 (P2) is connected to ECM pin 35(B) and decreases with the throttle position.

The sum of the two throttle position sensor voltages is thereby always approx. 5 V. The voltage from throttle position sensor 1 is used by ECM as a value for the current throttle position.

In the event of a serious fault in throttle control, it is switched off and ECM goes into limp-home mode.