Adaptation
The changing duration is calculated in real time by comparing the speeds of the input shaft and output shaft. The control module knows the gear ratio for the current gear and the target gear and can follow the change in gear ratio until the changing process is complete. The time it took to change gear is then compared with the desired value for the gear change and an adaptation is made.
The adaptation is done by correcting the requested pressure for the applied friction element solenoid and the correction is then used the next time a change is made between these gears. The adaptation value is saved in a non-volatile memory and must be zeroed using Tech 2 each time the TCM, gearbox or valve housing is changed and after SPS programming.
Note. The "Add" procedure must performed with Tech 2 after changing a complete gearbox including TCM or only the TCM or after SPS programming. A reset will then be done automatically.
After zeroing with Tech 2, it will usually only require a normal road test (about 10-15 min of varied driving) in normal conditions for the TCM to be able to adapt itself to the new conditions.
Manual gear changing can be accomplished with the selector lever in position M. Changing up and down is then controlled via a resistive multiplexed line from SLM to TCM. Certain models can be changed from the steering wheel with the selector lever is in M position; the change command is then sent from CIM. When changing with the steering wheel controls and the lever simultaneously, the lever will have priority. A manual gear change must be fully completed before TCM will accept a new change command. The current gear is shown on MIU. The highest permitted gear for pulling away is 3rd. For safety's sake, there will be a change down from gear 6, 5 and 4 automatically after kickdown and engine speed below 2000 rpm.
TCM sends continuous information on the bus concerning the engine torque allowed by the gearbox. When changing gear this value drops. this means that ECM limits engine torque if it exceeds this value.
The torque converter clutch is activated at steady speed in gears 3-6 when there is no need for any torque amplification. The slipping in procedure is regulated by comparing the speed on the input shaft with the engine speed obtained from ECM via the bus. Lock up will not work at temperatures below 15°C. If the brake is depressed or acceleration increases, the function will be activated.
If the temperature exceeds 150°C for longer than 2 seconds, bus message "TRANSMISSION OVERHEATING" will be sent from TCM. ICM shows the text on SID. Before this temperature message is shown in SID, the torque will have been dropped to 200 Nm for the purpose of protecting the gearbox from damage. The drop in torque takes place at 150°C.
A reverse detent function prevents reverse gear being engaged if the car is travelling faster than 7 km/h when the selector lever is moved from N to R.
Overrevving in gear position M will be prevented by not allowing changing down to take place if the speed is too high.
For high engine loads without a corresponding increase in speed one of two hill-climbing programs will be chosen. Gear changing is done at higher engine speeds and the gear will remain engaged for longer periods until the extra load ceases. These gearchange programs are used to avoid changing up and down unnecessarily, e.g. when driving up long inclines with trailer and to avoid overheating the gearbox oil.
Special gearchange programs are not activated at speeds above 150 km/h. If a special gearchange program is active when the speed increases to over 150 km/h, the program will continue, however, until the load has normalized.
If the power supply to TCM or to the solenoids is cut, the car can still be driven. Gear position D/M will give 2nd gear and P-R-N will work as normal but the gear will be engaged roughly as there is no regulation.
In case of a major fault in the gearbox, mechanical or electrical, TCM will cut the supply to the solenoids in a controlled manner. In most cases, the control module will attempt to maintain the current gear until the car has stopped. Subsequently, the control module will attempt to engage 2nd gear if D/M is selected. After this, the supply to the solenoids will be cut and the gearbox will lose all electrical control.
If an invalid gear ratio or the wrong gear is detected, the engine torque will be limited to 70 Nm in reverse and 100 Nm forward. For other faults, the torque will be limited to 180 Nm.
The car may only be towed with the front pointing in the direction of travel. The selector lever must be in position N. National regulations concerning towing speeds must be adhered to. If legislation allows, the highest permitted towing speed is 50 km/h. The longest permitted towing distance is 50 km. If the car should require towing for longer distances, the front wheels must be raised from the ground.
The engine cannot be started by pushing or towing the car.
For further information about the bus, see: Description of bus communication
| Bus message | Unit | Transmitter | User | Description |
|---|---|---|---|---|
| ABS active | On/Off | TCS/ESP | TCM | Used to inform TCM during ABS modulation, risk of rapid speed changes |
| ESP active | On/Off | TCS/ESP | TCM | Used to inform TCM during ABS modulation, risk of rapid speed changes |
| Wheel speed front left | Rpm | TCS/ESP | TCM | Used as reference speed value |
| Wheel speed front right | Rpm | TCS/ESP | TCM | Used as reference speed value |
| Automatic selector lever position | P, R, N, D, M, Movement in progress | TCM | SLM, ECM | Used by SLM to turn on the segment in question in the gear selector coulisse |
| Selector lever in position M | On/Off | SLM | TCM | TCM goes to M-mode |
| Ignition key may be removed | On/Off | SLM | CIM | Used by CIM as one of the criteria for allowing the key to be removed. Lever must be in P. |
| Brake lights active | On/Off | REC | SLM | Used by SLM to release the interlock solenoid for the gear selector lever. |
| Instrument lighting, rheostat value | % | ICM | SLM | Used by SLM to increase or reduce brightness in gear selector coulisse |
| Vehicle speed | Km/h | ECM | TCM | Used as reference speed value |
| Brake pedal, switch active | On/Off | ECM | TCM | Used by TCM to deactivate lock up. |
| Prevent shifting, request | On/Off | ECM | TCM | Used by TCM to avoid changing gear e.g. during ESP modulation |
| Accelerator pedal, kickdown | On/Off | ECM | TCM | Used by TCM for kickdown request. |
| Accelerator pedal position | % | ECM | TCM | Used by TCM (together with output shaft speed) to determine gear change points. If this information is incorrect, the gearbox will go into limp home. |
| Engine, limp home | On/Off | ECM | TCM | Informs TCM that the engine management system has gone into limp home. |
| Engine braking, fuel cut active | On/Off | ECM | TCM | Used by TCM to control slipping lock up |
| Engine torque, current | Nm | ECM | TCM | The value controls SLT requested pressure so that it does not exceed what is presently required by a friction element. |
| Engine torque, driver request | Nm | ECM | TCM | The value controls shifting points together with output shaft speed |
| Engine speed | Rpm | ECM | TCM | Used to modulate torque converter slip |
| Transmission, emission-related fault active | On/Off | TCM | ECM | ECM turns on Check Engine |
| Shifting pattern to prevent engine jolting, request | On/Off | ECM | TCM | Request from ECM to TCM that TCM should change shifting program to prevent engine jolting |
| Vehicle speed | Km/h | ECM | SLM | If the speed exceeds 12 km/h, SLM will activate the interlock solenoid for the gear selector lever, which is then not locked in N. |
| Brake pedal, switch active | On/Off | ECM | SLM | Informs SLM that the foot brake is applied, which is the criterion for SLM to release the interlock solenoid for the gear selector lever. |
| Key position, ignition switch | Lock, Off | CIM | TCM | The message wakes TCM (+15) and also informs it that the engine is being started (+50) |
| Sentronic, gear change request | None, up, down | CIM | TCM | The steering wheel buttons are connected to CIM. When the gear selector is in position M, TCM will use the value to change gear manually. |
| Immobilizer, transponder OK | On/Off | CIM | SLM | SLM does not release the interlock solenoid for the gear selector lever unless the transponder is approved. |
| Key position, ignition switch | Lock, Off, On, Start | CIM | SLM | SLM is awoken via bus |
TCM, BUS INFORMATION DESCRIPTION
To illuminate gear position symbols P-R-N-D-M+ and M
LEDs
The LEDs are powered by the Shift lever module (726)
The valve is used by TCM when activating C2. The pressure to SLC2 is then raised from system pressure to D-pressure. The valve is also used to apply pressure to brake B2 for engine braking in 1st gear.
Electromagnetic, normally open
Scheme 567
The control module activates the valve by applying B+ to it. The valve is powered from control module pin 5 in the connector in direct contact with the gearbox on the bottom of the control module. The valve is grounded in the valve housing.
| Pin no. | Interface | Description |
|---|---|---|
| 5 | B+ | Solenoid S1 |
PIN DESCRIPTION
Scheme 568
The valve is used together with S1 to apply pressure to brake B2 for engine braking in 1st gear.
Electromagnetic, normally closed.
The control module activates the valve by applying B+ to it. The valve is powered from control module pin 2 in the connector in direct contact with the gearbox on the bottom of the control module. The valve is grounded in the valve housing.
| Pin no. | Interface | Description |
|---|---|---|
| 2 | B+ | Solenoid S2 |
PIN DESCRIPTION
Scheme 569
The valve controls the pressure in brake B1. The valve is active in gear positions P, R, N, D (gears 1, 3, 4 and 5).
Electromagnetic, variable PWM controlled.
The control module activates the valve by pulsing it with B+ (300 Hz PWM). The valve is powered from control module pin 21 in the connector that makes contact directly with the gearbox on the bottom of the control module. The valve is grounded from pin 16. The current varies between 0-1000mA. The solenoid is normally open and the hydraulic pressure drops as the current increases.
| Pin no. | Interface | Description |
|---|---|---|
| 21 | B+ (300 Hz PWM) | Solenoid SLB1 |
| 16 | Ground |
PIN DESCRIPTION
Scheme 570
The valve controls the pressure in clutch C1. The valve is active in gear positions P, R, N, D (gears 5 and 6).
Electromagnetic, variable PWM controlled.
The control module activates the valve by pulsing it with B+ (300 Hz PWM). The valve is powered from control module pin 11 in the connector that makes contact directly with the gearbox on the bottom of the control module. The valve is grounded from pin 10. The current varies between 0-1000mA. The solenoid is normally open and the hydraulic pressure drops as the current increases.
| Pin no. | Interface | Description |
|---|---|---|
| 11 | B+ (300 Hz PWM) | Solenoid SLC1 |
| 10 | Ground |
PIN DESCRIPTION
Scheme 571
The valve controls the pressure in clutch C2. The valve is active in gear positions P, R, N, D (gears 1, 2 and 3).
Electromagnetic, variable PWM controlled.
The control module activates the valve by pulsing it with B+ (300 Hz PWM). The valve is powered from control module pin 17 in the connector that makes contact directly with the gearbox on the bottom of the control module. The valve is grounded from pin 18. The current varies between 0-1000mA. The solenoid is normally open and the hydraulic pressure drops as the current increases.
| Pin no. | Interface | Description |
|---|---|---|
| 17 | B+ (300 Hz PWM) | Solenoid SLC2 |
| 18 | Ground |
PIN DESCRIPTION
The valve controls the pressure in clutch C3. The valve is active in gear positions P, N, D (gears 1, 2, 4 and 6).
Electromagnetic, variable PWM controlled.
The control module activates the valve by pulsing it with B+ (300 Hz PWM). The valve is powered from control module pin 14 in the connector that makes contact directly with the gearbox on the bottom of the control module. The valve is grounded from pin 22. The current varies between 0-1000mA. The solenoid is normally open and the hydraulic pressure drops as the current increases.
| Pin no. | Interface | Description |
|---|---|---|
| 14 | B+ (300 Hz PWM) | Solenoid SLC3 |
| 22 | Ground |
PIN DESCRIPTION
The valve controls the gearbox system pressure. The value is controlled so that it is not higher than what is currently needed for any friction element. Brake B2 does not have its own pressure control valve and is therefore supplied by SLT.
Electromagnetic, variable PWM controlled.
Scheme 572
The control module activates the valve by pulsing it with B+ (300 Hz PWM). The valve is powered from control module pin 3 in the connector that makes contact directly with the gearbox on the bottom of the control module. The valve is grounded from pin 1. The current varies between 0-1000mA. The solenoid is normally open and the hydraulic pressure drops as the current increases.
| Pin no. | Interface | Description |
|---|---|---|
| 3 | B+ (300 Hz PWM) | Solenoid SLT |
| 1 | Ground |
PIN DESCRIPTION
The valve controls the pressure used for the torque converter clutch. The pressure is modulated so that full, partial or no engagement is achieved.
Electromagnetic, variable PWM controlled.
The control module activates the valve by pulsing it with B+ (300 Hz PWM). The valve is powered from control module pin 9 in the connector that makes contact directly with the gearbox on the bottom of the control module. The valve is grounded from pin 4. The current varies between 0-1000mA. The solenoid is normally closed and the hydraulic pressure rises as the current increases.
| Pin no. | Interface | Description |
|---|---|---|
| 9 | B+ (300 Hz PWM) | Solenoid SLU |
| 4 | Ground |
PIN DESCRIPTION
Scheme 573
To measure the speed of the gearbox input shaft. This value is used by TCM to calculate the actual gearchange time and to regulate lock up.
Magneto resistive, Hall effect. Measures a toothed wheel with 36 teeth.
Scheme 574
- Output shaft gear with output speed sensor
- C2 clutch drum with input speed sensor
The sensor is powered from TCM pin 12 and is grounded through pin 13.
| Pin no. | Interface | Description |
|---|---|---|
| 12 | Rotation speed signal | Power supply and rotation speed signal |
| 13 | Ground |
PIN DESCRIPTION
Scheme 575
To measure the gearbox output shaft speed. This value is used by TCM mainly to determine the gearchange points.
Magneto resistive, Hall effect. Measures a toothed wheel with 56 teeth.
- Output shaft gear with output speed sensor
- C2 clutch drum with input speed sensor
The sensor is powered from TCM pin 19 and is grounded through pin 20.
| Pin no. | Interface | Description |
|---|---|---|
| 19 | Rotation speed signal | Power supply and rotation speed signal |
| 20 | Ground |
PIN DESCRIPTION
To inform the control module if the current temperature. The value is used to correct the PWM ratio to the solenoids so that the gear changes are not affected by the viscosity of the oil. It is also used to activate the special gearchange program in case of overheating.
The sensor comprises an NTC resistor built into a plastic casing. The NTC resistor characteristics mean the resistance drops as the temperature rises.
The NTC resistor is supplied with 5V through a pull up from control module pin 8 and is grounded through pin 7.
| Pin no. | Interface | Description |
|---|---|---|
| 8 | Temperature signal | Temperature signal |
| 7 | Ground |
PIN DESCRIPTION
Scheme 576
To prevent the selector lever being moved from P or N on automatic cars before the brake pedal has been depressed.
Electromagnetic.
The solenoid is controlled by the Shift lever module (726). The selector lever can be released manually via the solenoid if there is an electrical fault.
Scheme 577
Operation of audio and telephone systems, changing up and down on automatic transmissions and horn switch.
The steering wheel buttons are resistive multiplexed (5V) and divided into 2 circuits; Sentronic/horn in one circuit and other buttons in the second. The 2 circuits have a common ground from CIM. Each circuit has an extra resistor for diagnosing a break in the circuit.
The lead for the Sentronic/horn is fed with 5V via a 560ohms resistor integrated in CIM. When the horn switch closes, the line is grounded and the voltage drops to 0V. For changing up and down respectively there are 2 switches and 2 resistors: one for up and one for down changes. Depending on the switch being pressed, the total resistance will change and therefore 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 coil spring to CIM. CIM sends the status of the horn and the other buttons on the bus.
The CIM (column integration module) powers the button unit with 5 volts: for audio and telephone on pin 1 and for Sentronic/horn on pin 4. A common ground goes to pin 2. Depending on the switch being pressed, the total resistance will change and therefore also the voltage.
Pin 3 receives a 12 volt PWM signal to control the brightness of the LEDs.
| Pin no. | Interface | Description |
|---|---|---|
| 1 | 5V | Audio and telephone |
| 2 | Ground | Common ground, LEDs and buttons |
| 3 | 12V PWM | LEDs |
| 4 | 5V pull up | Sentronic/horn |
PIN DESCRIPTION
Wiring diagram, power supply
Scheme 578
Controlling shifting points, system pressure and engagement of lock up.
Microprocessor with integrated Hall sensor.
Scheme 579
The TCM is mounted directly on top of the gearbox. The selector lever is integrated in the control module. The TCM is mounted so that the selector lever shaft goes through the control module. The selector lever position is calibrated with Tech 2, there is no mechanical adjustment.
An exterior 16-pin connector connects to the car's electrical system. Underneath the control module is another connector (22-pin) that connects directly to the gearbox. TCM makes contact with all the gearbox solenoids and sensors here.
Note. Magnetic fields from e.g. magnets and from high-current cables, such as starter cables and cables to auxiliary equipment, can interfere with the gear position sensor. A rule of thumb is max 1A per mm in distance from the control module. A starter cable carrying a current of 200A must therefore be kept at least 20 cm away from the control module.
The TCM has a microprocessor with clock, RAM memory and a programmable ROM. An internal bus connects the processor and memory with the I/O unit. The I/O unit reads values from the A/D converter for analogue inputs, digital inputs and bus, as well as activates the transistors' output stages.
Adaptive values are saved in a non-volatile memory (ROM). When changing gearbox, these values must be zeroed using Tech 2. After changing TCM they will be zeroed automatically after adding the control module using the "Add" menu in Tech 2.
Contacting the car's electrical system
| Pin no. | Interface | Description |
|---|---|---|
| 9 | Power ground | Power supply |
| 11 | +30 | Power supply |
| 1 | +15 | Signal |
| 7 | P-bus + | Signal to/from other control modules |
| 6 | P-bus | Signal to/from other control modules |
| 8 | P-bus + | Signal to/from other control modules |
| 14 | P-bus | Signal to/from other control modules |
| 3 | Selector lever | Sentronic's gear change request |
| 16 | Starter motor relay | Power supply in position P/N |
PIN DESCRIPTION
TCM contact directly to gearbox
| Pin no. | Interface | Description |
|---|---|---|
| 1 | SLT | Ground |
| 2 | S2 | Power supply + |
| 3 | SLT | Power supply + |
| 4 | SLU | Ground |
| 5 | S1 | Power supply + |
| 7 | Temperature sensor | Ground |
| 8 | Temperature sensor | Temperature signal |
| 9 | SLU | Power supply + |
| 10 | SLC1 | Ground |
| 11 | SLC1 | Power supply + |
| 12 | Input shaft speed | Rotation speed signal |
| 13 | Input shaft speed | Ground |
| 14 | SLC3 | Power supply + |
| 16 | SLB1 | Ground |
| 17 | SLC2 | Power supply + |
| 18 | SLC2 | Ground |
| 19 | Output shaft speed | Rotation speed signal |
| 20 | Output shaft speed | Ground |
| 21 | SLB1 | Power supply + |
| 22 | SLC3 | Ground |
PIN DESCRIPTION
Scheme 580
Scheme 581
| IMPORTANT | When handling the control module, it is important first to create a ground connection between yourself and for example the vehicle engine. Avoid touching the pins of the control module. |
To inform TCM that gear position "M" has been selected.
To inform TCM through a direct line that manual gear changing up or down is requested.
To inform Ignition switch module that gear position "P" has been selected.
To indicate with LEDs in the gear selector coulisse the gear position that is currently selected, P-R-N-D or M.
Microprocessor with integrated Hall sensor.
The SLM control module is powered with +30 on pin 2 from the electrical center 22, fuse 5. Grounding is done on pin 3, grounding point G41. Bus communication (I-bus) takes place on pin 12.
Communication regarding gear changes up or down in position "M" takes place from pin 7 on the SLM to pin 3 on TCM for FA 57 respectively pin 8 on TCM for AF 40.
Communication is resistive multiplexed. SLM has an internal 8.2 kohm resistor to B+ connected to the pin. This is connected in parallel with another resistor of 1.5 kohm when changing down. When changing up, a resistor of 4.4 kohm is connected. There is a 390 ohm resistor to ground in TCM. In this way, 3 normal voltage levels are generated corresponding to a untouched gear lever, M- and M+. Other voltage levels give a diagnostic trouble code.
| Pin no. | Interface | Description |
|---|---|---|
| 2 | + 30 | Supply from main fuse box 22 |
| 3 | Ground | Grounding point G41 |
| 12 | Bus | I-bus |
| 7 | Sentronic, gear change request | Changing up and down to TCM |
PIN DESCRIPTION
Scheme 582
Scheme 583
- Power supply, ground and bus connection
- Communication with TCM
The electrical center for most of the operations in the compartment and dashboard.
BCM control module 707 is located in the electrical center
Electrical center with relays, maxi and micro-fuses.
The 16 pin connector from the BCM 707 control module is connected directly to the electrical center.
The electrical center is fed with +30 voltage from the engine bay electrical center 342 and is connected to the dashboard harness via a 42 pin connector.
Scheme 584
The following current circuits are distributed by the electrical center
- Power supply +30, dashboard's electrical center
- Power supply +15, dashboard's electrical center
- Power supply +54, dashboard electrical center