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Remove/Install Integrated Starter Alternator Control Unit - AR15.40-P-0004MNO

Engine 176, 177 In Model 167 

MODIFICATION NOTES

16.06.2020 Operation step 1 changed Operation step 1  
06.02.2020 Nut, positive line/ground line (48V) to integrated starter alternator control unit Engine 176 BA15.40-P-1008-01T
Fig 1: Integrated Starter Alternator Control Unit Components Location - Engine 176, 177 In Model 167 (Shown On Engine 176)
G14790248Courtesy of MERCEDES-BENZ USA

Shown on Engine 176 

G14790249Courtesy of MERCEDES-BENZ USA

Shown on Engine 176 

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°. Open cap slowly and release the overpressure. 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
Notice  Notes on coolant   AH20.00-P-2080-01KOA
Notice  Information on preventing damage to electronic components due to electrostatic discharge   AH54.00-P-0001-01A
Notice  Notes on avoiding damage through contamination and foreign objects   AH00.00-P-5000-01A
  Notes on safety-relevant components   AH00.00-Z-0019-01A
REMOVINGINSTALLING Remove/install     
1 Remove Engine from front axle carrier. Engine 176 in model 167 AR01.10-P-2510MNO
    Engine 177 in model 167 AR01.10-P-2510MNP
2 Remove coolant lines (1, 2) from starter-alternator control unit (N129) and seal openings using suitable protective covers.   AR20.20-P-7441-01RQ
    SPECIAL TOOL Set of protective covers Fig 2
3 Remove coolant line (2) from starter-alternator control unit (N129) bracket and place to one side. TORQUE SPECIFICATION Screw, coolant line holder to starter-alternator control unit holder *BA20.20-P-1013-01Q 
4 Remove coolant line (1) from crankcase and place to one side. TORQUE SPECIFICATION Screw, holder of coolant lines to oil pan top section *BA20.20-P-1010-01Q 
5 Release and disconnect electrical connector (4).    
6 Open cover caps, remove nuts (3) and place electric lines (5) to one side. TORQUE SPECIFICATION Nut, positive line/ground line (48V) to integrated starter alternator control unit *BA15.40-P-1008-01T 
7 Remove bracket (7) and place electric lines (5) to one side. TORQUE SPECIFICATION Screw, holder of 48V ISA electronic wiring harness to Engine carrier/oil pan/cylinder head/electric refrigerant compressor *BA22.10-P-1002-02C 
8 Remove screws (10) and remove cap (11). INSTALLATION IMPORTANT : Replace seal.  
    TORQUE SPECIFICATION Bolt, terminal box cover to starter-alternator control unit *BA15.40-P-1004-02A 
9 Release and disconnect electrical connector (12). NOTES
Press release mechanism in direction of arrow (A).
Starter-alternator control unit (N129) will otherwise be damaged.
 
10 Unscrew screws (13). TORQUE SPECIFICATION Phase bolt on inverter/Integrated starter alternator *BA15.40-P-1007-02A 
11 Remove screws (14) and remove starter-alternator control unit (N129). INSTALLATION IMPORTANT : Replace seal.  
    TORQUE SPECIFICATION Bolt, starter-alternator control unit to bracket for starter-alternator control unit. *BA15.40-P-1008-02A 
12 Install in the reverse order.    
INSPECT Check     
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 danger zone. 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
13 Perform engine test run. While doing so, check engine for proper operation and leak tightness    
INTEGRATED STARTER ALTERNATOR

Number Designation Engine 176 Engine 177
BA15.40-P-1004-02A Bolt, terminal box cover to starter-alternator control unit Nm 8 8
INTEGRATED STARTER ALTERNATOR

Number Designation Engine 176 Engine 177
BA15.40-P-1007-02A Phase bolt on inverter/Integrated starter alternator Nm 11 11
ALTERNATOR

Number Designation Engine 176 Engine 177
BA15.40-P-1008-01T Nut, positive line/ground line (48V) to integrated starter alternator control unit Nm 16 16
INTEGRATED STARTER ALTERNATOR

Number Designation Engine 176 Engine 177
BA15.40-P-1008-02A Bolt, starter-alternator control unit to bracket for starter-alternator control unit. Nm 8 8
RADIATOR, COOLANT HOSES

Number Designation
 
Engine 176 in model 167 Engine 177 except in model 463
BA20.20-P-1010-01Q Screw, holder of coolant lines to oil pan top section Nm 8 8
RADIATOR, COOLANT HOSES

Number Designation Engine 176 in model 167 Engine 177 except in model 463
BA20.20-P-1013-01Q Screw, coolant line holder to starter-alternator control unit holder Nm 8 8
ENGINE SUPPORT (ENGINE SIDE)

Number Designation Engine 176 Engine 177
BA22.10-P-1002-02C Screw, holder of 48V ISA electronic wiring harness to Engine carrier/oil pan/cylinder head/electric refrigerant compressor M6 Nm 8 8
Fig 2: Identifying Set Of Protective Covers (001 589 06 91 00)
G14785718Courtesy of MERCEDES-BENZ USA