TCM, bus information

For further information on the bus, refer to BUS AND DIAGNOSTICS COMMUNICATION .

TCM, BUS INFORMATION DESCRIPTION

Bus message	Type of information	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	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
Atmospheric pressure	kPa	ECM	TCM	Used by TCM to go into high altitude shifting program due to reduced engine power
Vehicle speed	km/h	ECM	TCM	Used as reference speed value
Brake pedal, switch active	On/Off	ECM	TCM	Used by TCM for torque limitation, max 200 Nm, and engine brake
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 when kick down requested
Accelerator pedal position	%	ECM	TCM	Used by TCM (together with output shaft speed) to determine shifting points. If this information is incorrect, the transmission will go into limphome mode
Coolant temperature	Degrees C	ECM	TCM	Used by TCM for WUSP, Warm Up Shift Pattern.
Engine, limp home	On/Off	ECM	TCM	Informs TCM that the engine has gone into limp-home mode
Engine warmup cycle (OBD) ready	On/Off	ECM	TCM	Warm -up cycles are used for TCM fault handling. After 40 cycles, a fault code will be cleared if the fault has been rectified and Check Engine is not on for this fault
Engine braking, fuel cut active	On/Off	ECM	TCM	Used by TCM to control slipping lock up
Engine braking, slipping lock up	Permitted/Not Permitted	ECM	TCM	ECM synchronizes lock up with fuel cut during engine braking to prevent jarring
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
Shifting pattern for catalyst ignition, request	On/Off	ECM	TCM	Request that TCM should select special shifting program for faster catalyst ignition
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, On, Start	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