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Assignment Of Engine Fuse And Relay Module - GF54.15-P-1256-32FR

Model 257, 290 

IMPORTANT Relays J, K, L, M and O are located inside the housing and firmly soldered onto the PCB.

Fig 1: Engine Fuse And Relay Module - Model 257
G14549321IMPORTANTCourtesy of MERCEDES-BENZ USA
Slot Fuse Identification Circuit Wire Identification Fused component Fuse rating (A)
100 Electrical fuse 100 (K40/8f100) - - Spare  
101 Electrical fuse 101 (K40/8f101) 87M 1.5 RDGN Engine 256: 
Circuit 87M end sleeve (Z7/48z1)
15
        Engine 264: 
Fuel tank diagnostic module (A101)
 
        Engine 654, 656: 
CDI control unit (N3/9)
 
102 Electrical fuse 102 (K40/8f102) 87M 2.5 RDBU Engine 654, 656: 
CDI control unit (N3/9)
20
        Engine 177, 256: ME-SFI [ME] control unit (N3/10)  
      4.0 RDBU Engine 264: 
ME-SFI [ME] control unit (N3/10)
 
103 Electrical fuse 103 (K40/8f103) 87M 1.5 RDYE Engine 654, 656: 
CDI control unit (N3/9)
15
        Engine 264: 
ME-SFI [ME] control unit (N3/10)
 
        Model 257 with code U79 (BlueTEC (SCR) diesel exhaust gas cleaning, Generation 3): 
NOx sensor control unit downstream of SCR catalytic converter (N37/8) NOx sensor control unit upstream of diesel oxidation catalytic converter (N37/12)
 
      2.5 RDYE Engine 177: 
Fuel tank diagnostic module (A101) Oil sensor (oil level, temperature and quality) (B40)
 
        Engine 177: 
Coolant thermostat heating element (R48) Left thrust circulating air switchover valve (Y101/1) Right thrust circulating air switchover valve (Y101/2) Engine oil pump valve (Y130)
 
      4.0 RDYE Engine 256: 
ME-SFI [ME] control unit (N3/10)
 
104 Electrical fuse 104 (K40/8f104) 87M 1.5 RDBK Engine 654, 656: 
CDI control unit (N3/9) Circuit 87M end sleeve (Z7/75z1)
15
      4.0 RDBK Engine 177: 
Ignition coil, cylinders 5+6 (T4/2) Ignition coil, cylinders 7+8 (T4/3) Left intake camshaft solenoid (Y49/4) Left exhaust camshaft solenoid (Y49/6)
 
        Engine 256: 
ME-SFI [ME] control unit (N3/10)
 
        Engine 264: 
Potential distributor 2 power supply (X30/90)
 
105...109 Electrical fuse 105 (K40/8f105) - Electrical fuse 109 (K40/8f109)     Spare  
110 Electrical fuse 110 (K40/8f110) 30t 1.5 PKRD Model 257 with code 631 (LED static headlamp, left-hand traffic) or code 632 (LED static headlamp, right-hand traffic): 
Right front lamp unit (E2)
20
      1.5 GNRD With CODE 640 (High Performance LED) or CODE 641 (Dynamic left-hand traffic LED headlamp) or CODE 642 (Dynamic right-hand traffic LED headlamp)): 
Left front lamp unit (E1) Right front lamp unit (E2)
 
111 Electrical fuse 111 (K40/8f111) 30t 2.5 RDBK Wiper motor (M6/1) 30
112 Electrical fuse 112 (K40/8f112) - - Spare -
113 Electrical fuse 113 (K40/8f113) 50 2.5 VTWH Except code B01 (48V technology): 
Starter (M1)
30
114 Electrical fuse 114 (K40/8f114) 87 4.0 RDWH Model 257 with code 489 (AIR BODY CONTROL): 
AIR BODY CONTROL compressor (A9/1)
40
      2.5 RDGN Model 290 with engine 177: 
Low-temperature circuit circulation pump 1 (M43/6) Low-temperature circuit circulation pump 3 (M43/8)
20
115 Electrical fuse 115 (K40/8f115) - - Spare -
116 Electrical fuse 116 (K40/8f116) - - Spare -
117 Electrical fuse 117 (K40/8f117) 30t 0.5 RD Engine 256: 
Electric refrigerant compressor (A9/5)
7, 5
118 Electrical fuse 118 (K40/8f118) 87C 1.0 RDGN Low-temperature circuit circulation pump 1 (M43/6) 15
        Engine 256: 
Low-temperature circuit switchover valve (Y73/1)
 
        Model 290 with engine 177: 
Circuit 87C end sleeve (Z141/2z1)
 
119 Electrical fuse 119 (K40/8f119) 87C 1.0 RDBU Powertrain control unit (N127) Fan motor (M4/7) 15
        Engine 256, 264: 
Low temperature circuit circulation pump 2 (M43/7)
 
        Model 257 with code 2U1 (Radiator shutters): 
Upper radiator trim flap actuator motor (M2/38) Lower radiator trim flap actuator motor (M2/39)
 
        Model 290 with code U78 (AMG Sport exhaust system): 
Left exhaust flap actuator motor (M16/53) Right exhaust flap actuator motor (M16/54) Exhaust flap center actuator motor (M16/55)
 
        Model 257 with code U21 (AMG performance exhaust system): 
Left exhaust flap actuator motor (M16/53)
 
120 Electrical fuse 120 (K40/8f120) 30t 0.5 RDBU With code 597 (Windshield, heated) and code B01 (48V technology): 
Windshield heater control unit (N61)
5
121 Electrical fuse 121 (K40/8f121) 15M 0.75 RD Park pawl capacitor (C8) 10
122 Electrical fuse 122 (K40/8f122) 15M 1.0 PKRD Model 290 with code 467 (Electronic locking differential): 
Electric differential lock control unit (N3/2)
5
123 Electrical fuse 123 (K40/8f123) 15M 0.5 BKRD Front SAM control unit (N10/6) 5
124 Electrical fuse 124 (K40/8f124) - - Spare -
125 Electrical fuse 125 (K40/8f125) 15M 0.5 PKRD Powertrain control unit (N127) 5
        With code B01 (48V technology): 
48 V on-board electrical system battery (G1/3)
 
        Engine 654, 656: 
CDI control unit (N3/9)
 
        Engine 256, 264: 
ME-SFI [ME] control unit (N3/10)
 
        Engine 177: 
Drive Unit control unit (N145/1)
 
        With code M005 (4MATIC): 
All-wheel drive control unit (N45)
 
126 Electrical fuse 126 (K40/8f126) - - Spare -
127 Electrical fuse 127 (K40/8f127) 50 0.5 VTWH Except code B01 (48V technology): 
Voltage dip limiter (R62)
5
128 Electrical fuse 128 (K40/8f128) 15M 0.5 PKRD Exterior lights switch (S1) 5
129 Electrical fuse 129 (K40/8f129) 15M 0.5 RD Electronic Stability Program control unit (N30/4) 5
130 Electrical fuse 130 (K40/8f130) - - Spare -
132 Electrical fuse 132 (K40/8f132) 87 0.35 OG Model 257 with code 489 (AIR BODY CONTROL): 
AIR BODY CONTROL control unit (N51/3)
5
133 Electrical fuse 133 (K40/8f133) 30t 1.5 PKRD Model 257 with code 631 (LED static headlamp, left-hand traffic) or code 632 (LED static headlamp, right-hand traffic): 
Left front lamp unit (E1)
20
        With CODE 640 (High Performance LED) or CODE 641 (Dynamic left-hand traffic LED headlamp) or CODE 642 (Dynamic right-hand traffic LED headlamp)): 
Left front lamp unit (E1) Right front lamp unit (E2)
 
Relay Identification Designation
G Engine compartment circuit 15 relay (K40/8kG)
H Starter circuit 50 relay (K40/8kH)
I Reserve relay (K40/8kI)
J CPC relay (K40/8kJ)
K Reserve relay (K40/8kK)
L Reserve relay (K40/8kL)
M Reserve relay (K40/8kM)
N Circuit 87M relay (K40/8kN)
O Not assigned
P Backup relay (K40/8kP)
Q Not assigned
R Model 257 with code 489 (AIR BODY CONTROL), model 290 with engine 177: 
Relay R (K40/8kR)

IMPORTANT Relays J, K, L, M and O are located inside the housing and firmly soldered onto the PCB.