2014-2018 Smart Fortwo and Smart Forfour - Description of Fuses

Vehicle interior fuse and relay module



Fuses Specifications
No. A Description
1 20 Rear roof rack electrical connection
2 - -
3 - -
4 - -
5 25 Driver-side SAM control unit
6 25 Driver-side SAM control unit
7 25 Driver-side SAM control unit
8 15 Center SAM control unit
Radio
Radio over connector sleeve for terminal 15 R
9 - -
10 15 Horn
11 5 Battery sensor and driver-side SAM control unit
12 15 Front cigarette lighter with ashtray illumination
13 - -
14 20 Automatic transmission protected through connector sleeve for circuit 30
Diagnostic connector
Smart EQ:
   Fused circuit 30 connector sleeve
   Diagnostic connector
15 15 Supply for fused circuit 30 connector sleeve
16 5 Motor electronics protected through connector sleeve for circuit 30
Smart EQ: Supply for fused circuit 30 connector sleeve
17 15 Supply protected through connector sleeve for circuit 30
18 10 Brake lights switch
19 5 Outside mirror adjustment switch
20 3 Transponder coil
Electronic Stability Program control unit and brake light switch
Protected through connector sleeve for circuit 30
21 10 Light functions protected through connector sleeve for circuit 30
22 5 Steering wheel angle sensor
Dual-clutch transmission control unit
23 - -
24 15 Center SAM control unit
25 10 Center SAM control unit
26 15 Center SAM control unit
27 20 Center SAM control unit
28 10 Driver-side SAM control unit
29 10 Driver-side SAM control unit
30 15 Combination switch
Alarm siren
Supply for fused circuit 30 connector sleeve (valid for electric vehicle)
31 10 Instrument cluster and additional instruments
32 - -
33 5 Supplemental Restraint System control unit
34 5 Combination switch
35 5 Electrical power steering control unit
36 5 Center SAM control unit
37 30 Driver-side SAM control unit
38 40 Air conditioning power supply solenoid switch
39 30 Starter
Through starter relay
40 Smart EQ: Blower motor
 
1/1 10 Smart EQ: Electric vehicle circuit 30 connector sleeve supply
1/2 - Smart EQ:  
   Brake booster vacuum pump control unit
   Power electronics control unit
1/3 - -
1/4 20 Sound system amplifier control unit
1/5 5 Dual clutch transmission control unit
Smart EQ: Electric drive control unit
1/6 25 Left front power window motor and right front power window motor
1/7 5 Left electrically adjustable and heated outside mirror and right electrically adjustable and heated outside mirror
1/8 25 Smart EQ: 
   Front passenger seat heater control unit
   Driver seat heater control unit
1/9 - -
1/10 - Smart EQ: Steering wheel heater relay
 
2/1 20 Supply for soft top control drive unit
2/2 20 Supply for soft top control drive unit
2/3 - -
2/4 - -
Relay
K1 Heated rear window/outside mirrors
K2 Front power window
K3 Sliding roof
K4 Front headlamps
K5 Starter
K6 Fanfare horn
K7 Smart EQ: Steering wheel heater

Combustion engine fuse and relay module (F1)



Fuses Specifications
No. A Description
1 30 Heated rear window over relay for heated rear window/outside mirrors
2 30 Front passenger seat heater control unit
Driver seat heater control unit
Smart EQ: Brake booster vacuum pump control unit
3 25 Supply for Electronic Stability Program control unit
4 40 except Smart EQ:  Electrical fuse 1 and electrical fuse 2
25 Sliding roof relay
5 60 Supply for internal combustion engine fuse and relay module
6 50 Dual clutch transmission control unit
Protected through connector sleeve for circuit 30
40 Smart EQ: Vehicle interior fuse and relay module supply
7 30 Fan motor
Over fan relay
30 Fan solenoid switch
ICE combustion engine cooling
8 - -
9 60 USA: Secondary air injection pump
Smart EQ: 
   Heater for high-voltage battery
   Over heater relay for high-voltage battery
Relay
K1 Fan

Battery clamp fuse (F108)



Fuses Specifications
No. A Description
F1 200 Electrical fuse 3A (F108f3A) and electrical fuse 3B (F108f3B)
Smart EQ: 
   Power supply fuse and relay module (F1)
   DC/DC converter control unit
F2A 70 Vehicle interior fuse and relay module supply (F2)
Protected through connector sleeve for circuit 30
Connector sleeve for circuit 30
F2B 60 Electrical power steering control unit
F3A 70 Vehicle interior fuse and relay module supply (F2)
Ignition lock
Protected through connector sleeve for circuit 30
Connector sleeve for circuit 30
F3B 50 Electronic Stability Program control unit

Power supply fuse and relay module



Fuses Specifications
No. A Description
2 15 Smart EQ:
   Transmission mode recognition sensor
   Electric drive control unit
3 20 Fuel pump with fill level sensor and temperature sensor
40 Smart EQ: Electric vehicle drive motor fan relay
4 25 Supply for fused circuit 30 connector sleeve
30 Smart EQ: Battery cooling system coolant pumps relay
5 15 Supply for connector sleeves for circuit 87
15 Smart EQ: Battery cooling system coolant pump
6 15 Refrigerant compressor relay
5 Smart EQ:
   Battery management system control unit
   Electric drive control unit
7 10 Fan
Through fan relay
20 Smart EQ: Power electronics control unit power supply connector sleeve supply
8 10 Dual clutch transmission control unit
15 Smart EQ: Circuit 87 supply connector sleeve
Diode
1 except Smart EQ: Internal combustion engine relay module
2 USA: Supply for vacuum pump relay
Relay
K1 Engine function circuit 87
K2 Fan
K3 Ignition coils/fuel pump actuation
K4 Smart EQ: Battery cooling system coolant pumps