Alfa Romeo Selespeed

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Basic Selespeed Concept

Hydraulic system

System components

- Electro-hydraulic groep
- Solenoid valves and actuators
- Electric pump
- Measuring sensors
- Drivers controls
- Selespeed ecu pin out

System operation

- Overview of operation
- System activation
- Functioning with engine off
- Engine start
- Car start
- Car stop
- Semiautomatic MAN operation
- Automatic CITY operation
- Fault warnings
- Bump start
- Parking the car
- Towing

Routine maintenance

- Selespeed oil level

Faults and troubleshooting

- System diagnostics
- Fault downgrade table
- The car jerks
- Noisy gearbox
- The car doen't start
- Gears are not engaged
- Gears are not engaged CITY mode
- Gears are locked
- Car revs on start on
- Car goes to idle on its own
- During gear shifts car revs
- City> manual uncommanded
- Manual> City uncommanded
- Uncommanded engine switch off
- Selespeed fault flashes on display

Faults and troubleshooting

- P2 - Oil level check
- P3 - Oil leak check
- P4 - Oil pressure check
- P5 - Electric pump op check
- P6 - Clutch stop pin adjustment
- P7 - Brake pedal switch check
- P8 - Buttons on steering wheel and gear level check
- P9 - CITY button check
- P11 - Engagement of all gears with gear shift lever and engine off
- P14 - Clutch drag check
- P17 - Selespeed ecu errors
- P18 - clutch disk speed sensor check with road test

156 2.0 JTS

- Wiring diagrams

SYSTEM COMPONENTS - MEASURING SENSORS

Hydraulic circuit oil pressure sensor
It is installed directly on the hydraulic group.

Position of oil pressure sensor

It is installed directly on the hydraulic group. It consists of a capacitive sensitive element that generates a signal processed by a specific custom circuit inside the metal casing. It supplies the control unit CFC 208F with a voltage proportional to the pressure read, with reference to the supply voltage of the sensor. The supply voltage from CFC 208F is 5+/-0.5V with a draw of approx. 10 mA. The maximum pressure value read is approx. 80 bar.

Pressure sensor diagram

Actuators position sensor

The sensors that send the position of the gear selection, gear engagement and clutch control actuators to the Selespeed control unit are single ramp potentiometers installed directly on the electro-hydraulic group. They are powered with 5V+/-0.5V by the control unit CFC 208F. Maximum resistance between pins A-B is 1200 +/- 20Ohmat 20°C.

Location of actuator position sensors

The three sensors, of the same type, installed on the electro-hydraulic group are:
1. Gear selection position sensor
2. Gear engagement position sensor
3. Clutch position sensor

Clutch disk speed sensor (gearbox primary)
This is installed on the gearbox inlet, directly on the gear box. It is an electromagnetic sensor and sends a sinusoidal signal to the control unit CFC 208F that has a frequency in proportion to the speed of a pinion mounted on the gearbox primary shaft. The winding resistance is 1200 Ohm +/- 10% at 20°C. The air gap ranges between 0.2-1 mm.

Gearbox speed sensor position

Switch on brake pedal
Installed on the brake pedal unit.

Brake pedal switch

When the pedal is released it does not send any signal (NC) to the control unit CFC 208F. When the brake pedal is pressed the BRAKE lights switch on and the switch sends the car braked signal (12V) to control unit CFC 208F.

Door open switch
This reads the information (ON-OFF) regarding the state of the driver side door, sending an earth signal to the control unit CFC 208F when the door is open.