Mercedes-Benz S-Class (W222, C217, A217) (2014-2018) Fuse Diagram

Fuse box diagram (fuse layout), location, and assignment of fuses and relays Mercedes-Benz S-Class (W222, C217, A217) (S300, S320, S350, S400, S450, S500, S560, S600, S63 AMG, S65, Hybrid) (2014, 2015, 2016, 2017, 2018).

Mercedes-Benz S-Class (W222, C217, A217) (2014-2018)

Checking and Replacing Fuses

The fuses in your vehicle serve to close down faulty circuits. If a fuse blows, all the components on the circuit and their functions stop operating. If a fuse has blown, the inside element will be melted. Blown fuses must be replaced with fuses of the same rating, which you can recognize by the color and value. The fuse ratings are listed in the fuse allocation chart (located in a recess at the side of the fuse box in the trunk).

If a newly inserted fuse also blows, have the cause traced and rectified at a qualified specialist workshop, e.g. an authorized Mercedes-Benz Center.


  • Before changing a fuse, secure the vehicle against rolling away and switch off all electrical consumers.
  • Always disconnect the battery before servicing high current fuses.
  • Always replace faulty fuses with the specified new fuses having the correct amperage. If you manipulate or bridge a faulty fuse or if you replace it with a fuse with a higher amperage, the electric cables could be overloaded. This could result in a fire. There is a risk of an accident and injury.
  • Only use fuses that have been approved for Mercedes-Benz vehicles and which have the correct fuse rating for the system concerned. Otherwise, components or systems could be damaged.



  • F32/3 – Engine compartment prefuse box
  • K40/6 – Left fuse and relay module
  • K40/8 – Engine fuse and relay module



  • F1/3 – Right A-pillar fuse box
  • F32/4 – Vehicle interior prefuse box
  • F33 – Rear prefuse box
  • K40/5 – Rear fuse and relay module

Instrument Panel Fuse Box

The fuse panel is located on the driver’s side of the dashboard.

Instrument Panel Fuse Box Location

Do not use a pointed object such as a screwdriver to open the cover in the dashboard. You could damage the dashboard or the cover.

  • Open the driver’s door.
  • To open: pull cover (1) outwards in the direction of the arrow and remove it.
  • To close: clip in cover (1) on the front of the dashboard.
  • Fold cover (1) inwards until it engages.



Instrument Panel Fuse Box Diagram

Fused function:A
200Front SAM control unit40
201Front SAM control unit40
202Alarm siren5
203W222: Driver seat heater control unit30
204Diagnostic connector5
205Electronic ignition lock control unit7.5
206Analog clock5
207Climate control control unit20
208Instrument cluster7.5
209Front climate control operating unit5
210Steering column tube module control unit10
213Electronic Stability Program control unit25
217Japanese version: Dedicated Short-Range Communications control unit5
218Supplemental restraint system control unit5
219Weight sensing system (WSS) control unit5
Front passenger seat occupied recognition and ACSR
EBackup relay
FRelay, circuit 15R

Fuse box in the front-passenger footwell

Fuse box in the front-passenger footwell (location)

  • Open the front-passenger door.
  • Fold cover (1) down and remove it.

Fuse box in the front-passenger footwell (diagram)

  1. Circuit 30 “E1” connection
  2. Circuit 30g “E2” connection
Fused functionA
301Mirror taximeter5
302Right front door control unit30
303W222: Left rear door control unit30
C217, A217: Rear control unit
304W222: Right rear door control unit30
C217, A217: Rear control unit
305Driver seat control unit30
306Front passenger seat control unit30
307W222: Intelligent servo module for DIRECT SELECT20
C217, A217: Driver seat heater control unit30
308Front passenger seat heater control unit30
309Emergency call system control unit5
Telematics services communications module
HERMES control unit
310Stationary heater control unit25
311Rear blower motor10
312Overhead control panel control unit10
313Hybrid and Hybrid Plus: Power electronics control unit10
314A217: Antitheft alarm system (designation in coordination)7.5
315Powertrain control unit10
Valid for gasoline engine: ME-SFI control unit
Valid for engine 642, 651: CDI control unit
317W222: Panoramic sliding sunroof control module30
C217, A217: MAGIC SKY CONTROL control unit
318Audio/COMAND display15
319Panoramic sliding sunroof control module30
C217, A217: Panoramic roof roller sun blind control module
320Active Body Control control unit15
AIRmatic control unit (Valid except Active Body Control)
321C217, A217: Intelligent servo module for DIRECT SELECT20
322COMAND controller unit15
323Supplemental Restraint System control unit7.5
MF1/1Japan version: Dedicated Short-Range Communications control unit7.5
MF1/2Mono multifunction camera7.5
Stereo multifunction camera
MF1/3Rain/light sensor with additional functions7.5
Overhead control panel control unit
MF1/4Driver seat control unit7.5
MF1/5Front passenger seat control unit7.5
MF1/6Steering column tube module control unit7.5
MF2/1Perfume atomizer generator5
MF2/2Audio/COMAND control panel5
MF2/3Electronic Stability Program control unit5
MF2/4 Heads-up display5
MF2/5Hybrid and Hybrid Plus: Electrical refrigerant compressor5
MF3/1Front SAM control unit5
MF3/2Radar sensors control unit5
MF3/3COMAND fan motor5
MF3/4Driver side instrument panel button group5
Center instrument panel button group
MF3/5Rear air conditioning operating unit5
MF3/6as of 01.06.2016: Antenna changeover switch for telephone and stationary heater5


Interior prefuse box

Interior prefuse box

Fused functionA
I7Right A-pillar fuse box125
I2Left fuse and relay module125
I3No-load current shutoff relay connection-
C1Blower regulator40
I1Electronic Stability Program control unit40
I6Rear fuse and relay module60
I5Right A-pillar fuse box60
F32/4k2Quiescent current cutout relay

Engine Compartment Fuse Box

It is on the left-hand side of the vehicle, when viewed in the direction of travel.

Engine Compartment Fuse Box Location

Engine Compartment Fuse Box Location

  • Open the hood.
  • To open: release retaining clamps (1) and remove cover (2).
  • Use a dry cloth to remove any moisture from the fuse box.
  • Undo screws (3) on the fuse box.
  • Remove fuse box cover (4) forwards.
  • To close: check whether the seal is lying correctly in cover (4).
  • Insert cover (4) at the rear of the fuse box into the retainer.
  • Fold-down cover (4) of the fuse box and tighten screws (3).
  • Insert cover (2) and secure with retaining clamps (1).
  • Close the hood.

Engine Compartment Fuse Box Diagram



Fused functionA
100Hybrid: Vacuum pump40
101Connector sleeve, circuit 87/215
102Connector sleeve, circuit 87/220
103Connector sleeve, circuit 87M415
104Connector sleeve, circuit 87M315
105Valid for transmission 722.9: Transmission oil auxiliary pump control unit15
106Wiper park position heater25
107Valid for engine 277, 279: Starter/air pump electrical connection60
108Valid for SAE dynamic LED headlamp for right-hand traffic or Dynamic LED headlamp::20
   Left front lamp unit
   Right front lamp unit
Valid without SAE dynamic LED headlamp for right-hand traffic or Dynamic LED headlamp::
   Right front lamp unit
109Wiper motor30
110Valid for code SAE dynamic LED headlamp for right-hand traffic or Dynamic LED headlamp::20
   Left front lamp unit
   Right front lamp unit
Valid without SAE dynamic LED headlamp for right-hand traffic or Dynamic LED headlamp::
   Left front lamp unit
112Engine fuse and relay module5
114AIRmatic compressor40
115Left fanfare horn15
Right fanfare horn
116Hybrid: Vacuum pump relay5
118Hybrid: Electronic Stability Program control unit5
119Circuit 87/C2 connector sleeve15
120Circuit 87/C1 connector sleeve7.5
121Electronic Stability Program control unit5
122Hybrid: HYBRID relay5
123Night View Assist control unit5
124Hybrid: Vehicle interior and engine compartment electrical connector5
125Front SAM control unit5
126Powertrain control uni5
Valid for diesel engine: CDI control unit
Valid for gasoline engine: ME-SFI [ME] control unit
128Exterior lights switch5
129AHybrid: Starter circuit 50 relay30
129BValid except Hybrid: Starter circuit 50 relay30
GEngine compartment circuit 15 relay
HStarter circuit 50 relay
IBrake vacuum pump relay
JHybrid: HYBRID relay
KTransmission oil pump relay
LHorn relay
MWiper park position heater relay
NCircuit 87M relay
OValid except Hybrid: Starter circuit 15 relay
PSecondary air injection relay
QHybrid: Vacuum pump relay
RAIRmatic relay

Engine compartment prefuse box

Engine compartment prefuse box

  1. Connection, circuit 30 “B1”
  2. Connection, circuit 30 unlatched “B2”
Fused functionA
M3Hybrid: Electrical machine500
Valid except Hybrid: Alternator500
M1Hybrid: Electrical machine-
Valid except Hybrid: Starter-
MR5Electrical power steering control unit100
MR2Fan motor100
M4Hybrid: Fully integrated transmission control controller unit100
M2Valid for diesel engine: Glow output stage150
MR1Motor fuse and relay module60
MR4Valid for engine 277, 279: Fan motor150


Luggage Compartment Fuse Box

The fuse block is placed on the right-hand side of the trunk, when viewed in the direction of travel.

Luggage Compartment Fuse Box Location

  • Open the trunk lid.
  • To open: release cover (1) at the top right and left-hand sides with a flat object.
  • Open cover (1) downwards in the direction of the arrow.

Luggage Compartment Fuse Box Diagram

  1. Circuit 30 “E1” connection
  2. Circuit 30g “E2” connection
Fused functionA
400Parking system control unit (Active Parking Assist or code 360-degree camera)10
401Trunk lid control control unit5
402Rear entertainment controller unit7.5
404Armrest heater control unit7.5
405Sound system amplifier control unit7.5
Left front door tweeter control unit
Right front door tweeter control unit
408Tuner unit5
409360° camera control unit5
Reversing camera
410Camera cover control unit5
411Tire pressure monitor control unit5
412Rear seat heater control unit7.5
413Left rear display10
Right rear display
414Rear cellular telephone system antenna amplifier/compensator7.5
Rear mobile phone cradle
Rear mobile phone contact plate
Telephone module with Bluetooth (SAP profile) 
417Trailer recognition control unit20
420DC/AC converter control unit30
421Multicontour seat pneumatic pump30
422W222: Right rear door control unit30
424Rear SAM control unit40
426Bass speaker amplifier30
427Armrest heater control unit20
428Trailer recognition control unit15
429Rear cup holder10
430Cigarette lighter with ashtray illumination, rear15
Cigarette lighter with rear center console illumination
Left rear center console socket 12V (ashtray package/smoker package)
431Rear backrest refrigerator box15
432Rear SAM control unit10
433AdBlue control unit25
434AdBlue control unit15
435AdBlue control unit20
436Rear cup holder20
438C217 with engine 157: Right exhaust flap actuator motor7.5
439C217 with engine 157: Left exhaust flap actuator motor7.5
445Stationary heater radio remote control receiver5
446FM 1, AM, CL [ZV] and KEYLESS-GO antenna amplifier5
447Hybrid: Battery management system control unit7.5
451Trailer socket15
452Left rear bumper radar sensor5
Right rear bumper radar sensor
Center rear bumper radar sensor
453Left front bumper radar sensor5
Right front bumper radar sensor
454AdBlue control unit5
Fuel system control unit
455Fully integrated transmission control controller unit15
457Valid for lithium-ion battery: Starter battery capacitor7.5
460Front cigarette lighter with ashtray illumination15
461Right rear center console socket 12V15
Socket 12V
DC/AC converter control unit
462Luggage compartment socket15
464Trailer recognition control unit20
465Electric parking brake control unit30
466Left front door control unit30
467KEYLESS-GO control unit10
468Electric parking brake control unit30
469Fuel system control unit25
470Left rear seat heater control unit30
Rear seat heater control unit
471Right rear seat heater control unit30
472C217, A217: Rear control unit30
473Trailer recognition control unit20
475Sound system amplifier control unit40
476Sound system amplifier control unit40
477Active belt buckle control unit40
C217, A217: Rear control unit
478Left rear seat control unit30
479Active belt buckle control unit40
480Right rear seat control unit30
481Left front reversible emergency tensioning retractor5
482W222: MAGIC SKY CONTROL control unit5
C217, A217: MAGIC SKY CONTROL control unit7.5
483Right front reversible emergency tensioning retractor5
484Right rear seat control unit7.5
Left rear seat control unit
485Active belt buckle control unit5
   Battery management system control unit
   Power electronics control unit
487Electric parking brake control unit5
488Rear SAM control unit5
489Front long-range radar sensor5
490Multicontour seat pneumatic pump5
491Trunk lid control control unit40
492Right front reversible emergency tensioning retractor40
494Rear SAM control unit40
495Rear window heater40
496Left front reversible emergency tensioning retractor40
SVehicle interior circuit 15 relay
TRear window heater relay
U2nd seat row cupholder and sockets relay
VAdBlue relay
WCircuit 15R relay
X1 st seat row/trunk refrigerator box and sockets relay
YSpare relay

Rear prefuse box

Rear prefuse box

Fused functionA
I2Windshield heater control unit125
I7Hybrid: High-voltage disconnect device7.5
I4Rear fuse and relay module150
I6ECO start/stop function additional battery200
I7ECO start/stop function additional battery10
Front SAM control unit
Electronic ignition lock control unit
I7Front SAM control unit10
I8ECO start/stop function additional battery relay connection-
I5Hybrid: High-voltage pyrofuse triggered by Supplemental Restraint System control unit-
I9Decoupling relay connection-
F33k1Decoupling relay
F33k2ECO start/stop function additional battery relay