Remove/install integrated starter alternator control unit

AR15.40-P-0004MRT

Remove/install integrated starter alternator control unit

31.03.2020

Engine

256.9 in model 222

Modification notes

07.05.2019

Phase bolt on inverter

BA15.40-P-1008-02MRT

31.03.2020

Bolt, holder for wiring harness (integrated starter alternator/refrigerant compressor/transmission) to crankcase

BA15.40-P-1014-02MRT

1

Screw

2

Coolant line

3

Coolant line

4

Nuts

5

Screw

6

Electrical connector

7

Bracket

N129

Starter generator control unit

10

Bolts

13

Bolts

11

Cover

14

Bolts

12

Electrical connector

N129

Starter generator control unit

 Caution

Risk of injury caused by scraping or cutting body parts on sharp vehicle parts

Always wear protective gloves when working on or near sharp and non-deburred vehicle parts.
Deburr repair panels.

AS00.00-Z-0017-01A

Topical note

Information on preventing damage to electronic components due to electrostatic discharge

AH54.00-P-0001-01A

Topical note

Notes on avoiding damage through contamination and foreign objects

AH00.00-P-5000-01A

 

Remove/install

1

Disconnect ground line from battery.

AR54.10-P-0003LF

2

Drain off low-temperature circuit coolant.

AR09.41-P-6834MRT

 Installation: Only install lower engine compartment paneling after leak test.

3

Remove the catalytic converter.

AR49.20-P-0100MRT

4

Remove heat shield above starter-alternator control unit (N129).

 Screw, heat shield to crankcase/catalytic converter bracket/engine mount heat shield

*BA22.10-P-1004-02A

5

Remove coolant lines (2, 3) from starter-alternator control unit (N129) and seal openings with suitable stop plugs.

AR20.20-P-7441-01RQ

 Record plug

*129589009100

6

Remove coolant line (2) from timing case cover and place to one side.

 Bolt, coolant return line to timing case

*BA15.40-P-1009-02MRT

7

Remove coolant line (3) from crankcase and place to one side.

 Bolt, coolant feed pipe to crankcase

*BA15.40-P-1010-02MRT

8

Release and disconnect electrical connector (6).

9

Remove screw (1).

 Screw, ground line to right timing case/torque converter housing

*BA15.18-P-1002-03MRT

10

Unscrew nuts (4) and remove electric lines.

 Nut, circuit 40/41 to starter-alternator control unit

*BA15.40-P-1011-02MRT

11

Remove screw (5) and remove bracket from crankcase.

 Bolt, holder for wiring harness (integrated starter alternator/refrigerant compressor/transmission) to crankcase

*BA15.40-P-1014-02MRT

12

Remove wiring harness of integrated starter alternator (A79) and place to one side.

13

Remove bracket (7).

 Bolt, bracket to catalytic converter/engine carrier

*BA49.10-P-1002-02MRT

14

Remove screws (10) and remove cap (11).

 Installation: Replace seal.

 Bolt, terminal box cover to starter-alternator control unit

*BA15.40-P-1004-02MRT

15

Release and disconnect electrical connector (12).


Press release mechanism in arrow direction A.
The electrical connector (12) will otherwise be damaged.

16

Remove screws (13).

 Phase bolt on inverter

*BA15.40-P-1008-02MRT

17

Remove screws (14) and remove starter-alternator control unit (N129).

 Installation: Replace seal.

 Bolt, starter-alternator control unit to crankcase/timing case

*BA15.40-P-1005-02MRT

18

Install in the reverse order.

19

Read out and delete fault memory.



AD00.00-P-2000-04B

 Warning

Risk of accident from vehicle starting off by itself when engine running. Risk of injury (bruises and burns) resulting from working on the engine while it is being started or when it is running.

Secure vehicle to prevent it from starting off by itself. Wear closed and snug-fitting work clothes. Do not touch hot or rotating parts.

AS00.00-Z-0005-01A

20

Carry out engine test run and check engine for proper operation and leak tightness.

21

Install lower engine compartment lining.

AR61.20-P-1105LF

 48 V on-board electrical system subharness

Number

Designation

Engine 256 in model 222

BA15.18-P-1002-03MRT

Screw, ground line to right timing case/torque converter housing

Nm

25

 Starter-alternator

Number

Designation

Engine 256

BA15.40-P-1004-02MRT

Bolt, terminal box cover to starter-alternator control unit

Nm

8

 Starter-alternator

Number

Designation

Engine 256

BA15.40-P-1005-02MRT

Bolt, starter-alternator control unit to crankcase/timing case

Nm

8

 Starter-alternator

Number

Designation

Engine 256

BA15.40-P-1008-02MRT

Phase bolt on inverter

Nm

11

 Starter-alternator

Number

Designation

Engine 256

BA15.40-P-1009-02MRT

Bolt, coolant return line to timing case

Nm

8

 Starter-alternator

Number

Designation

Engine 256

BA15.40-P-1010-02MRT

Bolt, coolant feed pipe to crankcase

Nm

8

 Starter-alternator

Number

Designation

Engine 256

BA15.40-P-1011-02MRT

Nut, circuit 40/41 to starter-alternator control unit

Nm

16

 Starter-alternator

Number

Designation

Engine 256

BA15.40-P-1014-02MRT

Bolt, holder for wiring harness (integrated starter alternator/refrigerant compressor/transmission) to crankcase

Nm

12

 Engine support (engine side)

Number

Designation

Engine 256

BA22.10-P-1004-02A

Screw, heat shield to crankcase/catalytic converter bracket/engine mount heat shield

Nm

8

 Exhaust system

Number

Designation

Engine 256.9 in model 222

BA49.10-P-1002-02MRT

Bolt, bracket to catalytic converter/engine carrier

Nm

20