BMW M3 DCT User Manual

Table of Contents
M Double-Clutch Transmission
with Drivelogic
Subject	Page
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . .5
Special Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . .6
Principles of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . .8
Comparison of the M DCT to the Manual and SMG . . . . . . . . . . . .	. . . .9
Technical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . .10
System Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. .11
M DCT System Circuit Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . .12
E9x M3 M DCT System Circuit Bus Overview and Terminal Status . .14
Operation and Power Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . .16
Shifting Operation From 1st to 2nd Gear . . . . . . . . . . . . . . . . . . .	. . .20

System Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23

Housing Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23

Internal Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24

Automatic Parking Lock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27

Emergency Release of Parking Lock . . . . . . . . . . . . . . . . . . . . . . . . . .29

Mechatronics Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30

Sensors and Communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33

M DCT Transmission Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34

TorqueIntervention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34

LIN-bus Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34

M-Gear Selector Switch (M GWS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35

M GWS Shifter Sensor System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41

Transmission Oil System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42

Pressure and Flow Regulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42

Two-stage Transmission Oil Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45

Service Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48

Parking Lock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48

Car Wash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48

Transmission Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48

Identifying the Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49

Service Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50

Initial Print Date: 05/08

Revision Date:

Subject	Page
Possible Fault Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. .52
High TransmissionOil Temperature . . . . . . . . . . . . . . . . . . . . . . . . .	. .52
Internal TransmissionFaults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. .53
Faults Related to Implausible Readings . . . . . . . . . . . . . . . . . . . . . .	. .56

Subject

Page

BLANK PAGE

M Double-Clutch Transmissionwith Drivelogic

(M DCT Drivelogic)

Model: 4th Generation M3

Production: From Start of Production

After completion of this module you will be able to:

•Describe the operation of the M Double-Clutch Transmission with Drivelogic.

•Identify the Components of the M Double-Clutch Transmission with Drivelogic.

•Diagnose the operation of the M Double-Clutch Transmission with Drivelogic.

4

M DCT Drivelogic

Introduction

BMW has introduced the new generation of sequential transmissions. The M DoubleClutch Transmissionwith Drivelogic (M DKG) GS7D36SG is available as an option on the entire E9x M3 series and is referred to as M DCT Drivelogic.

The M double-clutch transmission combines the benefits of a sequential M transmission with that of an automatic. Like the SMG, it can be used in automatic mode "Drive" and in manual mode "Sequential".

There are 5 Drivelogic programs in automatic “Drive” mode and 6 Drivelogic programs in “Sequential” mode. In sequential mode shifting can either be done with the new electronic sports shift lever, exclusive to the BMW M3, or with paddle shifters on the steering wheel. The main characteristic of this system is that there is no longer an interruption in driving force during the shifting operation.

Shifting is controlled by the M DCT electronics and executed by the M DCT hydraulic components. These are combined into one mechatronics module and integrated into the transmission. The M DCT has a dedicated system to directly lubricate all of the relevant transmission components. The transmission oil temperature is regulated by a special two stage cooling system.

An electric automatic parking lock has been integrated into the system. Selection of the driving programs and gears are controlled using the (M GWS) electric gear selector switch. Different driving modes and settings can be selected through the controller and the fifth settings menu of the CID (option dependent).

M3 vehicle with the new Getrag DKG GS7D36SG double-clutch transmission (M DCT)

5

M DCT Drivelogic

Special Features

GS7D36SG M double-clutch transmission features:

• Hydraulically operated double (wet) clutches

• Integrated mechatronics module, that consists of the M DCT electronics and the M DCT hydraulic components

• Internal direct lubrication of key transmission areas and components

• Special two-stage oil cooling system

• New M DCT electronic gear selector switch M GWS

• Automatic parking lock mechanism

• Drive shaft length has been adapted (shortened) to fit the M DCT transmission

• Fully variable M limited-slip differential with a modified gear ratio of 3.154 (without M DCT 3.846) and modified housing cover

M DCT Internal Structure

6

M DCT Drivelogic

M DCT Applications

Transmission

Model

Engine/torque

Transmittable

torque rating

E90 M3

S65B40O0

GS7D36SG

E92 M3

520 Nm

400 Nm

E93 M3

SMG/M DCT History

Series

Model

Engine

Predecessor

Basic

Introduced

manual transmission

transmission

1st generation

E36

M3

S50B32

Sequential M transmission

GS6S420BG

10/1996

Not US

E46

M3

S54B32O0

2nd generation

GS6S420BG

03/2001

Sequential M transmission

06/2003

E85

Z4

M54B25/30

Sequential manual

GS6S37BZ

04/2003

transmission

E6X

525i, 530i,

M54B25/30

Sequential manual

GS6S37BZ

09/2003

530i

N52B30O0

transmission

E6X

545i, 645Ci

N62B44O0

Sequential manual

GS6S53BZ

09/2003

550i, 650i

N62B48O1

transmission

E6X

M5/M6

S85B50O0

3rd generation

GS7S47BG

09/2005

Sequential M transmission

7

M DCT Drivelogic

Principle of Operation

The M DCT consists of two sub-transmissions, each with its own clutch. Clutch 1 with sub-transmission 1 and clutch 2 with sub-transmission 2. Sub-transmission 1 consists of the gears 1, 3, 5, 7 and Reverse while sub-transmission 2 consists of gears 2, 4 and 6. This means that the your next gear is always pre-selected in the other sub-transmission, regardless of whether you are shifting up or down (with the exception of "R").

For example, while still in the acceleration phase of the currently selected gear, if on subtransmission 1 the next logical gear on sub-transmission 2 is engaged in advance, in a process similar to the Shift Overlap function of an automatic transmission.

Precise control of the clutches when upshifting will allow the driving force to be transferred very quickly and smoothly from sub-transmission 1 to sub-transmission 2 without an interruption in driving power. This results in significant benefits not only for the available driving force but also in terms of shift comfort.

By combining the seamless driving force and comfort of the automatic with the direct connection to the engine as a manual, M DCT provides the benefits of both transmissions.

Simplified drawing of the M DCT functional principle

A

1	2
3	4

B

1

3

5

7

R

2

4

6

C

TT07-1380

Index	Explanation	Index	Explanation
A	Engine S65	1	Clutch 1
B	Double-clutch transmission	2	Sub-transmission 1
C	Live axle	3	Clutch 2
		4	Sub-transmission 2

8

M DCT Drivelogic

Comparison of the M DCT to the Manual and SMG

Diagram showing the driving force of one shift event of

M DCT compared to SMG and manual transmissions

1
	2	3	t
			4
Index	Explanation	Index	Explanation
1	Driving force	4	Manual transmission
2	Double-clutch transmission (M DCT)	t	Time (one shift event)
3	Automated transmission (SMG)

Note: Smooth gear changing without loss of driving force becomes clear when compared to the previous manual and SMG transmission.

9

M DCT Drivelogic

TechnicalData

A 7 speed manual transmission with wet double-clutch, parking lock, integrated mechatronics module and sport gear ratio.

	Description	Unit of Measurement
	Specified torque [Nm]	520
	Maximum engine speed [rpm]	9000
	Dry weight without dual mass flywheel [kg]	77
	Transmission ratio [:1]	Ratio
	1st gear:	4.780
	2nd gear:	3.056
	3rd gear:	2.153
	4th gear:	1.678
	5th gear:	1.390
	6th gear:	1.203
	7th gear:	1.000
	Reverse gear:	4.454
	Shifting options	E9x M3: R-N-D/S with selectable
		Drivelogic program
	Control	Electrohydraulic
	Full oil capacity with transmission oil cooler	9
	(liter)
	Oil grade: special new	BMW designation DCTF-1
	M DCT long-term oil

10

M DCT Drivelogic

System Overview.

The components of the 2-stage transmission oil cooling system are built into the left side of the transmission.

External left side view of the M DCT transmission

The mechatronics module is integrated into the transmission on the right side. The oil lines lead to the oil to air heat exchanger (coming from the left side of the transmission).

External right side view of the M DCT transmission

The electronic M DCT transmission control is networked with the M gear selector switch and the interfaces to the E9x M3 vehicle electrical system. The E9x-M3 vehicle electrical system has been expanded to include the M double clutch transmission.

11

M DCT Drivelogic

M DCT System Circuit Diagram

	2
	4
1	3

PT-CAN

		DME
DSC
		DKG
5	6	WUP
		CAS3
	PT-CAN
	K-CAN
		Kl. 30g
7		8
SZL		9
10
11		12
FRM		LINBus-
		13
		GWS
14	15
		16
		Kl. 58g
		17
	F-CAN	DSC_SEN

12

M DCT Drivelogic

TT07-0884

	M DCT System Circuit Diagram Legend
	Index	Explanation	Index	Explanation
	1	DSC control unit (Dynamic Stability Control)	10	Door contact switch
	2	Auxiliary water pump	11	Footwell module
	3	M DCT electronics (integrated into the	12	M gear selector switch (M GWS)
		Mechatronics module)
	4	DME/ECM (Digital Engine Electronics)	13	Parking lock electromagnet
	5	Instrument cluster	14	Brake light switch
	6	CAS control unit (Car Access System)	15	Accelerator pedal module
	7	Steering column switch cluster	16	Drivelogic program selector button
	8	Diagnostics interface	17	DSC sensor unit
	9	Junction box electronics

13

M DCT Drivelogic

14M

DCTDrivelogic ASP

2x

SBFA FRM CID

SMC KOMBI

2x

E92

GBFA SMFA

E92

GBBF FLA

E93

MW-SEN

4x

E93

E90/E92

SINE

USIS

RLS FZD

PDC CAS3

TAGE

2x

8x (4x)

IHKA CA

E93

CTM

TT07-1325_2

D-CAN

K-CAN

MOST

PT-CAN

F-CAN

JB

EDC-K

DCTKG

GWS

SZL

QLT

DSC

DSC-SEN IBS

LLS

G

DME

protokoll)

BSD

LIN-Bus

Lo-CAN

Status Terminal and Overview Bus Circuit System DCT M M3 E9x

	Index	Explanation	Index	Explanation
	ACSM	Advanced Crash and Safety	JB	Junction box
		Management (E93 only)
	ASP	Outside mirrors	KOMBI	Instrument cluster
	CA	Comfort Access	LLS	Idle speed actuator
	CAS3	Car Access System 3rd generation	LWS	Steering angle sensor
	CCC	Car Communication Computer	MW-	Microwave sensors (E93 only)
			SEN
	CDC	(Compact) CD changer	MRS5	Multiple restraint system, 5th generation
				(E90 and E92 only)
	CID	Central information display	OC3	Seat occupancy detector mat (US only)
	DCT	M DCT electronics (integrated	PDC	Park distance control
		into the transmission)
	CON	Controller	QLT	Quality, level, temperature oil sensor
	CTM	Convertible roof module (E93 only)	RAD	Radio2
	DME	Digital motor electronics	RLS	Rain light sensor
	DSC	Dynamic Stability Control	ROC	Rollover controller (E93 only)
	DSC-	DSC sensor	SBFA	Switch block, driver's door
	SEN
	EDC-K	Continuous Electronic Damping Control	SBX	High-level interface box
			High
	EDR	Throttle valve actuator motor	SDARS	Satellite tuner (US only)
	EKP-	Electric fuel pump control unit	SINE	Emergency power siren with
	SG			integrated tilt alarm sensor
	FLA	High beam assistant	SMBF	Passenger's seat module
	FRM	Footwell module	SMC	Stepper motor controller
	FS	MOST direct access	SMFA	Driver's seat module
	FZD	Roof function center	SZL	Steering column switch cluster
	GBBF	Seat belt extender controller,	TAGE	Outside door handle electronics
		front passenger (E92 only)
	GBFA	Seat belt extender controller, driver (E92 only)	TCU	Telematics Control Unit
	GWS	M gear selector switch	TOP-	Top-HiFi amplifier
			HiFi
	IBS	Intelligent battery sensor	USIS	Ultrasonic passenger-compartment
				sensor (E90/E92 only)
	IHKA	Integrated automatic
		heating/air conditioning system
				15
				M DCT Drivelogic

Operation and Power Flow

2

3

																						2				R		1					3										7
								4																																	7
																															5
				1																																							8
																																								6
												6					4																			5
																																								7
Schematic Structure of the M DCT																							9					10												1719
																																																			TT07-
Index					Explanation																				Index																			Explanation
1	Central input shaft with clutch input																								6																			Countershaft
2					Clutch 1																				7																			Constant gears
3					Clutch 2																				8																			Output shaft
4					Inner input shaft 2																				9																			Sliding clutches
5					Inner input shaft 1																				10																			Parking lock

Operation

The driving force is guided into the transmission by a central input shaft (1) through wet clutches 1 and 2, which are integrated into the transmission. Clutch 1 (2) transmits the power to inner input shaft 1 (5).

Clutch 2 (3) transmits the power to inner input shaft 2 (4).

The torque is then transferred to the output shaft (8) via the countershaft (6). The constant gears (7) are always engaged regardless of the gear selected. The countershaft and the output shaft are also always engaged.

The respective gear pairs are selected via the sliding clutches (9).

The 7th gear is the direct gear, the sliding clutch connects inner input shaft 1 directly to the output shaft.

The parking lock (10) is located directly on the output shaft. 16

M DCT Drivelogic

Power Flow

M DCT "Neutral"

1st gear power flow

2nd gear power flow

															2				R				1		3
																																		7
								6				4																	5

TT07-1379

															2				R				1	3
																																7
										6
												4																5

TT07-1322

														2				R				1				3
																																		7
									6
											4																			5

1324-TT07 17

M DCT Drivelogic

3rd gear power flow

4th gear power flow

5th gear power flow

18

M DCT Drivelogic

													2				R				1			3
																														7
										6
												4													5

TT07-1363

																	2				R				1				3
																																					7
									6					4																			5

TT07-1364

									2				R				1			3
																											7

6	4	5

TT07-1365