Ignition switch interlock
An interlock and security feature (ignition switch interlock) is mechanically connected to the ignition switch by a cable. The ignition switch interlock is controlled by the position of the lock cylinder in the ignition switch and by the position of the gear selector. This means that the gear selector must be in the P-position for the ignition key to be removed from the ignition switch. The ignition key must be turned to position I or II before the lever can be moved from the P-position. The ignition switch interlock is used only in combination with shift-lock.
The gear-shift position sensor has a park / neutral position (PNP) function to prevent the engine being started with a gear selected.
This function prevents the engine being started unless the P or N positions are selected. This prevents the car from lurching forwards when started.
For further information, see CENTRAL ELECTRONIC MODULE (CEM) (2005-2006) .
There are two functions for adaptation in the transmission control module (TCM) software which can be activated
- Resetting adaptation - carried out after replacing internal components or the entire transmission the transmission control system the transmission fluid the entire transmission the transmission control module (TCM).
- Adaptation function - This function helps the mechanic to adapt the transmission. It makes it easier to reset the function of the transmission after repair or replacement of, for example: the transmission control system the transmission fluid the entire transmission the transmission control module (TCM).
When the adaptation function has been activated, the test drive instructions must be followed. The following shifts can be adapted
- 1-2
- 2-3
- 3-4
- 4-5
- N-D
- 5-4
- 4-3
- 3-2
- 2-1
- N-R
- Neutral Control engagement and disengagement, if equipped.
While the car is in this mode, the orange/yellow warning lamp in the center of the combined instrument panel is used to indicate when each shift has been adapted to its target value.
When the orange/yellow warning lamp (triangle) flashes after each of the listed shifts, the adaptation is complete.
Note. The function is only available in certain software versions.
Adaptation of the transmission is activated via the VIDA vehicle communication socket.
Scheme 690
A counter for transmission oil quality is built into the software for the transmission control module (TCM). The counter counts up the amount of time the oil is above a certain temperature. When the counter has reached the maximum value, the diagnostic trouble code (DTC) for an oil change is stored in the control module. When replacing transmission fluid the counter must be reset to prevent a diagnostic trouble code (DTC) being stored incorrectly. This applies when the transmission fluid is changed and when the fluid is changed during a repair.
The reset function is activated via the VIDA vehicle communication socket.
An emergency program is activated to deal with the fault when the transmission control module (TCM) detects a transmission fault (permanent fault). If the transmission control module (TCM) detects a permanent fault, an emergency mode is activated. The transmission control module (TCM) then implements corrective action to protect the transmission, while leaving the car in the best possible drivable condition. Minor malfunctions do not activate an emergency program. There are different programs depending on the type of fault
- Emergency mode
- Limp-home mode.
Emergency mode is activated for minor faults and the Limp-home mode for the most serious faults. If the malfunction is intermittent, the transmission control module (TCM) returns to normal operation the next time the ignition is switched on.
Emergency mode
The warning lamp in the combined instrument panel comes on and a or text message is displayed for diagnostic trouble codes (DTCs) stored in the transmission control module (TCM).
The transmission shifts in all gears but transmits no signal to the lock-up solenoid. This means that lock-up is not available.
Limp-home mode
The warning lamp in the combined instrument panel comes on or a text message is displayed for diagnostic trouble codes (DTCs) stored in the transmission control module (TCM).
The transmission control module (TCM) interrupts the activation of all solenoids. This means that no shifting is possible. The transmission operates only in 3rd gear in positions 3 and L, 4th gear in position D and reverse in position R. Shifting can only be carried out manually between 3rd and 4th gear and reverse gear.
No control of line pressure solenoids SLS and SLT. Maximum system pressure constantly which results in harsh upshifting and downshifting and harsher shifts when engaging P-R, N-R and N-D.
Scheme 691
AW55-50 (and AW50AWD) is a 5-speed electronically controlled automatic transmission with a lock-up function for the three highest gears. The transmission control module (TCM) adapts the gear changes to ensure that the correct gear is selected for the driving mode, engine load, driver requirements, speed etc. This gives good fuel economy combined with increased comfort by ensuring smoother gear changes and lower noise levels.
The transmission control module (TCM) receives information about the desired gear position and driving mode from the driver. In conjunction with the signals from a number of sensors in the transmission and the engine control system, unlike with a purely hydraulically controlled transmission, this allows the control module to calculate the optimal shifting points and engagement of lock-up. The control module allows for small changes in the operating conditions and adapts the various transmission functions to ensure that the correct gear is always selected in relation to the driving mode selected by the driver.
This adaptability guarantees smooth and consistent gear shift quality throughout the operational life of the transmission.
In order to precisely determine the gear shift and lock-up engagement points based on the driving mode selected, the control module receives and processes information about the following
- Selected gear position - from the gear-shift position sensor
- Selected driving mode economy/sport - reactive function programmed in the control module which is controlled by the speed at which the accelerator pedal (AP) is depressed. Quick "pedal movement" = sport mode. Winter (W) mode is activated using a switch on the gear selector assembly
- Vehicle speed - from the brake control system via the Controller area network (CAN)
- Transmission input shaft RPM - from the transmission speed sensor
- The transmission output shaft RPM - from the transmission output speed sensor
- The engine speed (RPM) and torque and throttle opening - from the engine management system via the Controller area network (CAN)
- If the brake pedal is depressed and to what extent - from the brake control system via the Controller area network (CAN)
- If the accelerator pedal (AP) is depressed and to what extent - from the engine management system via the Controller area network (CAN)
- Transmission fluid temperature - from the temperature sensor in the transmission
- Engine coolant temperature - from the engine control module (ECM) via the Control area network (CAN).
Scheme 692
The following components are included in the control system for automatic transmissions
- Transmission control module (TCM) - Controls activation and deactivation of the solenoids by processing the signals from components such as the transmission input and output speed sensors and the temperature sensor. Also stores adaptive data as well as diagnostic trouble codes (DTCs) and frozen values for diagnostics
- Shift solenoid, S1 - Controls shifting in the transmission
- Shift solenoid, S2 - Controls shifting in the transmission
- Shift solenoid, S3 - Controls shifting in the transmission
- Shift solenoid, S4 - Controls shifting in the transmission
- Shift solenoid, S5 - Controls shifting in the transmission
- Lock-up solenoid, SLU - Controls the lock-up function and is also used for certain shifts
- Line pressure solenoid, SLT - Controls the transmission line pressure and neutral control
- Line pressure solenoid, SLS - Controls the transmission shifting pressure and is activated for certain gears
- Transmission input speed sensor (input shaft speed) (1) - Provides the transmission control module (TCM) with information about the input shaft speed from the engine
- Speed sensor (output shaft speed) (2) - Provides the transmission control module (TCM) with information about the output shaft speed from the transmission
- Oil temperature sensor (3) - Provides the transmission control module (TCM) with information about the oil temperature of the transmission
- Gear-shift position sensor (4) - Provides the transmission control module (TCM) with information about the selected gear position
- Gear selector module (GSM) - Provides the transmission control module (TCM) with information about the Geartronic mode and winter mode (W) amongst others.
The table below summarizes the input signals to and output signals from the transmission control module (TCM). The signal types are divided into directly connected signals, serial communication and Controller area network (CAN) communication. The illustration below displays the same information with the Volvo component designations.
| Input signals | Output signals |
|---|---|
| Directly connected | Directly connected: (power supply unless otherwise stated) |
| Speed sensor, input shaft (7/61). Provides information about the transmission input speed. Use to calculate the shifting process and to run diagnostics for the hydraulic/mechanical functions in the transmission. Speed sensor, output shaft (7/62). Provides information about the transmission output speed. Use to calculate the vehicle speed and to run diagnostics for the hydraulic/mechanical functions in the transmission. Oil temperature sensor (7/74). Provides information about the transmission oil temperature. Gear-shift position sensor (3/71). Provides the transmission control module (TCM) with information about the selected gear position of the transmission. Enables starting only in position P and N. Four trailing contacts are grounded in a unique pattern for each gear. | Shift solenoids, S1-S5 (8/38-39, 8/72-74). The transmission control module (TCM) checks which gear is active by activating the solenoids in different patterns. Lock-up solenoid, SLU (8/40). Adjusts the line pressure to a lock-up pressure. Also used for certain shifts. Line pressure solenoid, SLS (8/41). Adjusts the line pressure to a shift pressure and is activated for certain gears. Line pressure solenoid, SLT (8/71). Adjusts the linear line pressure when shifting. |
| Via serial communication | Via serial communication |
| Gear selector module (GSM) (3/156). Provides data about the status of the winter (W) mode button and the control signal during geartronic shifting. | Gear selector module (GSM) (3/156). Controls the solenoid for the shift-lock function, 8/36. Activated by a signal from the central electronic module (CEM). |
| Via Controller Area Network (CAN) | Via Controller Area Network (CAN) |
| Electronic throttle module (ETM) (4/50) / Electronic throttle unit (6/120) via the engine control module (ECM) (4/46): Throttle opening, used to calculate gear changes. Sport mode and kick-down Accelerator pedal (AP) position, used to calculate gear-shift timing. Steering wheel module (SWM) (3/130), via the central electronic module (CEM) (4/56). Cruise control, used to calculate acceleration depending on the position of the Resume and Set buttons. Brake control module (BCM) / ABS control module (4/16). Provides information about the vehicle speed and also the difference in speed between the left and right-hand wheels. Prevents upshifting if the difference in speed is above 40 km/h to protect the differential in the transmission. Engine control module (ECM) (4/46): Stop lamp switch ON/OFF, used during torque converter lock-up Engine coolant temperature (ECT), used for diagnostics for the transmission temperature sensor and for catalytic converter start-up (Cat-start) Engine speed (RPM) >400 RPM = engine running. Used to start the transmission oil pressure and diagnostic functions Engine speed (RPM), used to check the slipping rate of the torque converter and the pressure build up, affecting the shifting comfort Kick-down. If the accelerator pedal (AP) is depressed and the throttle is wide open the engine control module (ECM) transmits a signal to the transmission control module (TCM) about kick-down Current engine torque, used to check the line pressure. | Brake control module (BCM) / ABS control module (4/16): Current gear, used to transmit a signal not to regulate when shifting Vehicle speed, used as back-up. Engine control module (ECM) (4/46): Transmission temperature, used to compensate increased load at low oil temperatures Selected gear, used by the engine so that the engine can compensate for different loads Lock-up, used by the engine so that the engine can compensate for different loads Next gear planned by the transmission control module (TCM), used by the engine so that the engine can compensate for different loads The request about reduced engine torque when shifting, the engine reduces the engine torque when shifting Torque limiting request, the engine limits the engine torque, depending on the current gear and if winter mode (W) is selected Current gear selector lever position. Used to show the lever position in the driver information module (DIM) Lights the malfunction indicator lamp (MIL) in the driver information module (DIM). Checking the malfunction indicator lamp (MIL), lamp lights in the event of emission related faults. Driver information module (DIM) (5/1): Current gear selector lever position. Used to show the lever position in the driver information module (DIM) Via the central electronic module (CEM), checking the warning lamps. The warning lamp lights orange in the event of a fault Via the central electronic module (CEM), text message in the driver information module (DIM). The driver can receive up to five error messages from the transmission control module (TCM). Rear electrical module (REM) (4/58). The transmission control module (TCM) transmits signals via the central electronic module (CEM) to light the back-up (reversing) lamp. |
Scheme 693
Using this function, the status of the control module input and output signals can be continuously read off.
For further information about parameters, see Description of parameters .
This function allows components to be activated so that their functions can be checked.
For further information about activations, see Description of activations .
This function can be used to continuously read off the values and status of the control module's input and output signals.
The following parameters can be read off
- The number of remote controls
- The number of the remote control NOTE: One of the remote control buttons must be activated when reading off.
- The activated buttons on the remote control NOTE: One of the remote control buttons must be activated when reading off.
- Power supply to mass movement sensor (MMS), status NOTE: Listed as On or Off. The mass movement sensor module (MMS) is supplied with voltage (On) when the alarm is activated and the sensors are connected.
- Alarm status NOTE: Indicates the alarm setting and alarm sensor setting. Six states can occur: Alarm status 1: Not activated and not deployed, connected sensors. Alarm status 2: Activated and not deployed, connected sensors. Alarm status 3: Activated and not deployed, disconnected sensors. Alarm status 4: Activated and deployed, connected sensors. Alarm status 5: Activated and deployed, disconnected sensors. Alarm status 6: Not activated and not deployed, disconnected sensors.
- Front left reading lamp, status
- The switch for the front left reading lamp
- Front right reading lamp, status
- Switch for the front right reading lamp
- Rear left reading lamp, status
- The switch for the rear left reading lamp
- Rear right reading lamp, status
- The switch for the rear right reading lamp
- The switch for the general lighting
- Extended X-supply, status NOTE: X-supply supplies power to the sunroof, mirror lamps and rain sensor module (RSM). X-supply is active when the controller area network (CAN) is active, and for a short time after the controller area network (CAN) is no longer active. This time varies and depends on a number of parameters.
- Local lighting, status
- The degree of anti-dazzle for the rear view mirror NOTE: The parameter can only be read off when the engine is running and back-up (reverse) gear is not selected. 100% means that the rear view mirror is fully dimmed. 0% means that the rear view mirror is not dimmed.
- Supply voltage, sun roof
- NOTE: The following parameters for the sun roof are read off from a separate vehicle communication input for the upper electronic module (UEM).
- Button activation, forward
- Button activation, backward
- Button activation, tilt
- Button activation, auto
- Motor, forward
- Motor, backward.
- NOTE: The following parameters for tire pressure monitoring can only be read off on vehicles with TPMS.
- Last received sensor ID
- Last stored tire pressure
Note. A short delay can occur before a component is activated. Remote control activations can only be carried out if the key is not in the ignition. Lock activations can only be carried out if the doors are shut.
With this function the components and functions associated with the upper electronic module (UEM) can be activated.
The following components / parameters can be activated in alternative ways
- General lighting, directly to the lamp
- Front left reading lamp, directly to the lamp
- Front right reading lamp, directly to the lamp
- Rear left reading lamp, directly to the lamp
- Rear right reading lamp, directly to the lamp
- Extended X-supply
- Power supply to mass movement sensor (MMS)
- Seat belt reminder
- Indicates that the passenger airbag (PAD) is disconnected (from 2005-)
- Remote control, activate the button
- Local lighting
- NOTE: The following activations for the sun roof can be made from a separate vehicle communication input for the upper electronic module (UEM).
- Button activation, forward
- Button activation, backward
- Motor, forward
- Motor, backward.