E7050 Automatic transmission (Q-System)

Description

An electronic management system supervises and governs the operation of the AISIN automatic transmission.

An electronic control unit manages a complex operating logic which enables the transmission to be used either in totally "assisted" conditions, typical of a conventional automatic transmission, and in manual mode which allows sequential engagement of the gears and a more sporty style of driving.

The electronic control unit dialogues with the engine management control unit via two dedicated lines (CAN), and receives the engine rpm, fuel injection, throttle position and engine temperature signals.

Several sensors on the gearbox provide data on its operation and on the oil temperature: the control unit calculates the most suitable gear ratio and the locked condition of the hydrodynamic torque converter, sending the appropriate commands to the solenoids, also located on the gearbox;

It also drives, when necessary, a gearbox oil cooling fan.

For more details, see DESCRIPTION AND OPERATION: 2135 Automatic transmission external controls .

The system is also controlled by means of two relays located in the engine compartment near the battery.

The supply lines to the control unit and the various system components (sensors and actuators) are protected by a specific maxifuse and other jumper fuses located next to the junction unit.

Description of operation

The control unit of the AISIN electronic automatic transmission M55 monitors and governs the entire automatic transmission management system.

The control unit is supplied directly by the battery via the line of maxifuse O/A located on the battery (connector B99 D),at pin 12 of connector A of M55.

The supply controlled by the ignition (15/54) reaches pin 25 of connector A of M55.

Pins 2 and 8 of connector A of M55 are earthed.

The control unit M55 is connected to the selector lever position sensor located on the gearbox (unit L50, connector A): the unit receives an ignition-controlled supply (15/54) at pin 9, while pin 10 is earthed.

Pins 3, 5, 8 and 11 of L50 connector A send the signals corresponding to P, D, N and R respectively, which are connected to control unit M55, at pins 3 and 16 of connector A and 7 and 16 of connector B.

Pins 1 and 4 of L50 connector A are connected to the reverse gear sensor, and they send signals to turn on the reversing light ( Wiring diagram E2022 REVERSE LIGHT ).

Pin 2 of L50 connector A gives a safety signal (gear in N or P) for the starting enablement relay J05 which gives the starting enablement: pin 50 of the starter motor A20 ( Wiring diagram E5010 IGNITION AND RECHARGING ).

The control unit M55 - connector A - also connects to the solenoid unit L50 - connector B - which contains the control valves, pressure regulator and some sensors:

• the solenoid control signals come from pin 13 (for the gear change solenoid L1), pin 26 (for the gear change solenoid L2), pin 26 (for the torque converter lock solenoid L-UP) and pin 15 (for solenoid E/B);
• pin 11 of connector A of M55 supplies the pressure control solenoid, whose control signal comes from pin 1 of connector A of M55;
• pins 5 and 18 of connector A of M55 connect to the oil temperature sensor located next to the solenoids in L50.

Pins 4 and 12 of connector B M55 are connected to the car speed sensor (gearbox output) K77.

Pins 4 and 12 of connector B M55 are connected to the car speed sensor (gearbox output) K77.

Pins 3 and 11 of connector B M55 are connected to the gearbox speed input sensor K78; pin 2 of connector B M55 provides the signal screening earth.

Pin 9 of connector A of M10 receives the signal coming from the brake lights switch I30, with the supply controlled by the ignition (INT) from fuse F1 of the junction unit B1 ( Wiring diagram E2021 STOP LIGHT ).This signal controls the locking of the torque converter (L-UP).

The gear controls assembly H37 receives an ignition-controlled supply (15/54) and is connected to the control unit M55 to indicate the gear engagement request: these signals are sent to pins 13, 8, 10, 15 and 14 of connector A of M55; pin 7 of the connector A of M55 receives the P engaged signal.

The selector H49 is for selecting the various operating modes; it receives an ignition-controlled supply (15/54) and is connected to control unit M55 at pin 5 of connector B (SPORT/CITY function) and pin 14 of connector B (ICE function).

Control unit M55 governs a series of safety checks:

• shift lock (lever locked if ignition is not on (MAR) and brake pressed): sends a signal from pin 21 of connector A to the speed control unit H37;
• key lock (key locked if the gear selector is not set to P): sends a signal from pin 20 of connector A which controls the lock electromagnet L55 built into the ignition switch;
• doors open buzzer: the signal that the driver's door is open - lock N50 - reaches pin 6 of connector A of M55; the command for the buzzer, located in the instrument E15, is sent from pin 10 of connector A; the same line also sends signals for the display and for the "automatic transmission fault" warning light.
• oil overheating: if the gearbox oil is overheating (detected by the sensor in the above-mentioned unit L50, a command is issued from pin 19 of connector A to the specific relay J86, supplied under ignition control (15/54) via the line protected by the fuse F4 located in unit B98 A, which controls the appropriate fan N49.

Control unit M55 is equipped with a self-test system that may be used by connecting the unit to connector R10: this receives signals from pin 23 connector A of control unit M55.

Control unit M55 is connected to the engine management control unit M10. This connection is via the CAN line from pins 1 and 9 of connector B of M55, to pins 11 and 12 of connector D of M10.

Wiring diagram

Components

Component location