Part 2

Planetary gear, animation (Continued)

Solenoid valves SLS, TCM FA 57 (531)

Location

Solenoid valves, TCM (531)





Main use
To regulate the oil pressure to the various clutches/brakes in the transmission.

Type
Electromagnetic, PWM governed.





Activation
The solenoid is governed from pin 26 (B) on TCM using a 300Hz PWM voltage. Grounding takes place on pin 36 (B) on TCM. The current varies between 0-1000 mA. The solenoid is open when current is not applied. 0A = high oil pressure 1000mA = low oil pressure.








Solenoid valves SLT, TCM FA 57 (531)

Location

Shift solenoid, S1-S5 (531)





Main use
To regulate the transmission system pressure.

Type
Electromagnetic, PWM governed.





Activation
The solenoid is governed from pin 35 (B) on TCM using a 300Hz voltage. Grounding takes place on pin 15 (B) on TCM. The current varies between 0 - 1000 mA. The solenoid is open when current is not applied. 0A = high oil pressure 1000mA = low oil pressure.








Solenoid valves SLU, TCM FA 57 (531)

Location

Solenoid valves, TCM (531)





Main use
To regulate the oil pressure to the lock-up clutch.

Type
Electromagnetic, PWM governed.





Activation
The solenoid is governed from pin 25 (B) on TCM using a 300Hz PWM signal. Grounding takes place on pin 12 (B) on TCM. The current varies between 0-1000 mA. The solenoid is closed when current is not applied. 0A = low oil pressure 1000mA = high oil pressure.








Speed sensor, gearbox input shaft, FA 57 (532)

Location

Speed sensor, input shaft, transmission casing (532)

Main use
To measure the speed of the transmission input shaft. This value is used by TCM.





Type
Magneto resistance, Hall effect. Detects rotation of 12-tooth wheel.

Activation
The sensor is powered from pin 32 (B) on TCM and the sensor signal is received on pin 22 (B) on TCM.











Speed sensor, gearbox output shaft, FA 57 (533)

Location

Speed sensor, output shaft, transmission casing (533)

Main use
To measure the speed of the transmission output shaft. This value is used by TCM.





Type
Magneto resistance, Hall effect. Detects rotation of 18-tooth wheel.

Activation
The sensor is powered from pin 33 (B) on TCM and the sensor signal is received on pin 23 (B) on TCM.











Temperature sensor, gearbox oil, FA 57 (535)

Location

Transmission fluid temperature sensor (535)

Main use
To inform the control module of the current oil temperature.





Type
The sensor is an NTC resistor in a metal casing. The characteristics of the NTC resistor mean that the resistance drops as the temperature rises.

Activation
The NTC resistor is powered with 5V through a pull-up from control module pin 21(B) and is grounded through pin 31(B).











Switch unit, steering wheel (633)

Location

Switch unit, steering wheel (633)

Main function
Control of audio/navigation, phone, car settings, up and down shifting of automatic transmission and horn switch.

Type
The steering wheel buttons are resistive multiplexed (5V) and divided into 2 circuits; switches for Sentronic, horn and SET in one circuit and other buttons in the second. The 2 circuits have a common ground from the CIM. Each circuit has an extra resistor for diagnosing an open circuit.

The lead for the Sentronic/horn/SET is fed with 5V via a 560 Ohms resistor integrated in CIM. When the horn switch closes, the line is grounded and the voltage drops to 0V. For up and down shifting respectively there are 2 switches and 2 resistors: one for up and one for down shifting. Depending on the switch being pressed, the aggregate resistance will change and thereby also the voltage.

The buttons have integrated LEDs so that the symbols can be seen in the dark. The LEDs are powered by the CIM. All the leads go via a spring-loaded contact to CIM. CIM sends the status of the horn and the other buttons on the bus.





Electrical connections
The CIM (steering column control module) supplies 5 volts to the keypad, for audio/navigation, phone and car settings on pin 1 and for Sentronic/horn/SET on pin 4. Common ground is supplied to pin 2. Depending on the switch pressed, the aggregate resistance will change and thereby also the voltage.

Pin 3 receives a 12 volt PWM signal to control the brightness of the LEDs.








Wiring diagram, power supply