Remove/install integrated starter alternator control unit

AR15.40-P-0004MSA

Remove/install integrated starter alternator control unit

31.07.2020

Engine

256.9 in model 213, 238, 257, 290

Modification notes

14.07.2020

Insertion of an operation step variant for the removal/installation of the catalytic converter / exhaust gas aftertreatment unit

Operation step 3.1 / 3.2

31.03.2020

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

BA15.40-P-1014-02MRT

1

Coolant line

2

Coolant line

3

Nuts

4

Electrical connector

5

48 V wiring harness

6

Bracket

7

Bracket

N129

Starter generator control unit

10

Screws

13

Screws

11

Cover

14

Screws

12

Electrical connector

N129

Starter generator control unit

 Warning

Risk of injury to skin and eyes suffering scalding from contact with hot coolantspray. Risk of poisoning from swallowing coolant.

Do not open cooling system unless coolant temperature is below 90 °C. Open cap slowly and release the pressure. Do not pour coolant into beverage containers.
Wear protective gloves, protective clothing and safety glasses.

AS20.00-Z-0001-01A

 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

Notes on safety-relevant components

AH00.00-Z-0019-01A

 

Remove/install

1

Disconnect ground line of the battery (G1).

Engine 256.9 in model 213

AR54.10-P-0003LW

Engine 256.9 in model 238

AR54.10-P-0003LWO

Engine 256.9 in model 257, 290

AR54.10-P-0003FR

2

Drain off low-temperature circuit coolant.

AR09.41-P-6834MSA

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

3.1

Remove the catalytic converter.

Engine 256.9 in model 213, 238
up to model year 2020
Engine 256.9 in model 257, 290

AR49.20-P-0100MSA

3.2

Remove exhaust gas aftertreatment unit.

Engine 256.9 in model 213, 238
as of model year 2020

AR49.20-P-1500MSA

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 (1, 2) from the starter-alternator control unit (N129) and seal openings using suitable protective covers.

AR20.20-P-7441-01RQ

 Set of protective caps

*001589009100

6

Remove coolant line (2) from the timing case cover, place to one side and seal openings with suitable protective covers.

AR20.20-P-7441-01RQ

 Bolt, coolant return line to timing case

*BA15.40-P-1009-02MRT

 Set of protective caps

*001589009100

7

Remove coolant line (1) from the crankcase, place to one side and seal openings with suitable protective covers.

AR20.20-P-7441-01RQ

 Bolt, coolant feed pipe to crankcase

*BA15.40-P-1010-02MRT

 Set of protective caps

*001589009100

8

Release and disconnect electrical connector (4).

9

Open cover caps of the electric lines, unscrew nuts (3) and remove electric lines from the starter-alternator control unit (N129).

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

*BA15.40-P-1011-02MRT

10

Remove bracket (7) and place 48 V wiring harness (5) to one side.

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

*BA15.40-P-1014-02MRT

 M61

*BA00.10-P-1002-04A

11

Remove bracket (6).

 Nut/bolt, holder for catalytic converter to crankcase

*BA49.10-P-1007-02P

12

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

 Installation: Replace seal.

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

*BA15.40-P-1004-02MRT

13

Release and disconnect electrical connector (12).


Press release mechanism in arrow direction A.
Otherwise, damage to the starter-alternator control unit (N129) will occur.

14

Remove screws (13).

 Phase bolt on inverter

*BA15.40-P-1008-02MRT

15

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

16

Install in the reverse order.

17

Read out and delete fault memory.



Engine 256.9 in model 213

AD00.00-P-2000-04B



Engine 256.9 in model 238

AD00.00-P-2000-06LWO



Engine 256.9 in model 257, 290

AD00.00-P-2000-06FR

 Warning

Risk of burn injuries, suffocation and poisoning when working on the exhaust system and the components connected to it. Risk of suffocation and risk of poisoning caused by inhalation of gaseous and solid components of the exhaust. Risk of poisoning caused by skin contact with solid components of the exhaust.

Wear protective clothing and safety glasses. Use the extraction system. Move people out of the hazard area.

AS49.00-Z-0001-01A

 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

18

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

 Metric screws/bolts and nuts as per MBN 10 105, 10 143

Number

Designation

8.8

10.9

BA00.10-P-1002-04A

M61

Nm

9

13

 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

Model 213 with engine 256

Model 238 with engine 256

BA49.10-P-1007-02P

Nut/bolt, holder for catalytic converter to crankcase

Nm

20

20

 Exhaust system

Number

Designation

Model 257 with engine 256

Model 290 with engine 256

BA49.10-P-1007-02P

Nut/bolt, holder for catalytic converter to crankcase

Nm

20

20