Mercedes-Benz B-Class Fuse Box Locations and Diagrams (2005-2011)

The first-generation Mercedes-Benz B-Class (W245), produced from 2005 to 2011, introduced a new level of flexibility and practicality in the compact premium MPV segment. With its sandwich-floor design, elevated seating position, and efficient engine options, the W245 offered a spacious interior while maintaining a compact footprint ideal for urban driving. Its blend of safety, innovation, and comfort made it a popular choice among families and city commuters alike.

In this article, you will find fuse box diagrams for the Mercedes-Benz B-Class, covering models B160, B170, B180, and B200 for the years 2005, 2006, 2007, 2008, 2009, 2010, and 2011. These diagrams provide essential information about the fuse layout, making it easier for owners and technicians to locate and understand the purpose of each fuse and relay in the vehicle.

What’s Included:

Fuse Box Diagrams – Clear and detailed visuals showing the placement and function of each fuse, relay, and circuit breaker.
Fuse Panel Locations – Guidance on where to find the fuse panels inside the vehicle, including under-dash and engine bay locations.
Fuse Assignments – Comprehensive breakdowns of what each fuse and relay controls to assist in diagnostics and repairs.

Whether you’re replacing a faulty fuse, diagnosing an electrical issue, or performing scheduled maintenance, this guide will help ensure your Mercedes-Benz B-Class (W245) continues to deliver reliable performance.

Keep your B-Class in top shape with this complete fuse panel, fuse box, and relay chart guide!

The cigar lighter (power outlet) fuses in the Mercedes-Benz B-Class are located in the Passenger Compartment Fuse Box.:
- Fuse №38: Front Cigar Lighter
- Fuse №53: Rear Cigar Lighter / Interior Socket

What’s Included

Passenger Compartment Fuse Box

Fuse box location

The fuse box is located under the floor near the passenger seat (or near the driver’s seat on RHD).
Remove the floor panel, cover, and soundproofing.

The location of the fuses in the passenger compartment: Mercedes-Benz B-Class (2006-2011)

Fuse box diagram

Assignment of the fuses in the passenger compartment

№	Fused function	Amp
1	2005-2008: Stop light switch	10
1	Light and vision package (2005-2008): Stop light switch 2009-2011: Stop light switch	5
2	Heated rear window	25
3	Instrument cluster EIS [EZS] control unit	7.5
4	EIS [EZS] control unit Electric steering lock control unit	15
5	Automatic air conditioning and Comfort automatic air conditioning: HEAT control and operating unit Automatic air conditioning: AAC [KLA] control and operating unit Comfort automatic air conditioning: Comfort AAC [KLA] control and operating unit	7.5
6	Left fanfare horn Right fanfare horn	15
7	Fuel pump relay	25
8	Overhead control panel control unit	25
9	ESP and BAS control unit	40
10	Blower regulator/interior wiring harness connector	40
11	Valid for engine 266: Circuit 87 relay, engine	30
11	Valid for engine 640: Circuit 87 relay, engine	40
12	Steering column module Multifunction steering wheel (2005-2008)	5
13	Left front door control unit	25
14	Right front door control unit	25
15	ESP and BAS control unit	25
16	Data link connector Parktronic system (PTS) control unit (2005-2008)	10
17	Rotary light switch	5
18	Valid for transmission 711, 716: Backup lamp switch	7.5
19	Micromechanical turn rate sensor AY pickup	5
20	Restraint systems control unit	7.5
21	Starter relay	30
22	Instrument cluster	7.5
23	2005-2008: Washer nozzle heating	7.5
23	Valid for engine 640 as of 1.9.08: Fuel filter condensation sensor with heating element	20
24	Electric power steering (ES) control unit	7.5
25	Stop light switch ESp and BAS control unit	7.5
26	Valid for transmission 722: Electronic selector lever module control unit	7.5
27	Valid for transmission 722: CVT (continuously variable automatic transmission) control unit	10
28	Rotary light switch	5
29	SAM control unit	30
30	Circuit 87F relay	25
31	2005-2008: Central gateway control unit (vehicles up to 30.11.05), Rotary light switch 2009-2011: Automatic light switch daylight sensor, Rain/light sensor	5
32	Valid for engine 266: ME-SFI [ME] control unit	7.5
33	Radio Radio and navigation unit COMAND operating, display and control unit (Japan)	15
34	Left rear door control unit	25
35	Right rear door control unit	25
36	2005-2008: Cell phone separation point Trailer control unit	7.5
36	2009-2011: Trailer control unit PTS control unit	10
37	Restraint systems control unit Front passenger seat occupied recognition sensor Front passenger seat occupied and child seat recognition sensor	7.5
38	Front cigar lighter with ashtray illumination	25
39	Wiper motor	25
40	Louvered sunroof: Overhead control panel control unit	7.5
40	Lamella roof: Overhead control panel control unit	25
41	Liftgate wiper motor	15
42	Glove compartment illumination with switch Left and right vanity mirrors illumination Footwell illumination switch (driving school package) Pedal operation monitor switch (driving school package) VICS+ETC voltage supply separation point (Japan)	7.5
43	Valid for engine 266: Terminal 87M1e connector sleeve Bivalent natural gas drive (2009-2011): Terminal 87M1e connector sleeve	15
43	Valid for engine 640: Terminal 87M1e connector sleeve	7.5
44	Valid for engine 266: Terminal 87M2e connector sleeve	15
44	Valid for engine 640: Terminal 87M2e connector sleeve	20
45	Valid for engine 640: CDI control unit	25
46	2005-2008: Telephone control unit, (Japan) E-net compensator Universal Portable CTeL Interface (UPCI [UHI]) control unit	7.5
46	2009-2011: Bass module speaker (Japan)	25
46	2009-2011: Amplifier for sound system	40
47	Telephone control unit, (Japan) Universal Portable CTEL Interface (UPCI [UHI]) control unit Cell phone separation point Voice control system (VCS [SBS]) control unit	7.5
48	ATA [EDW]/tow-away protection/interior protection control unit Alarm signal horn with additional battery	7.5
49	Upper control panel control unit Left front seat heated cushion (2005-2008) Left front backrest heated cushion (2005-2008) Right front seat cushion heater element (2005-2008) Right front backrest seat cushion heater element (2005-2008)	25
50	2005-2008: CD changer VICS+ETC voltage supply separation point (Japan) 2009-2011: Media interface control unit Digital TV tuner Digital Audio Broadcasting control unit	7.5
50	Valid for government vehicles (2009-2011): Roof light bar Circuit 30 connector sleeve	30
51	Canada (2009-2011): Weight Sensing System (WSS) control unit Valid for government vehicles (2009-2011): Special signal system control panel	10
52	VICS+ETC voltage supply separation point (Japan) (vehicles up to 31.5.06)	5
52	Spare (vehicles as of 1.6.06)	7.5
52	Emergency call system control unit (USA) (vehicles up to 31.5.06)	7.5
53	Rear cigar lighter with ashtray illumination Interior socket	30
54	Amplifier for sound system Bass module speaker	25
54	Valid for government vehicles (2009-2011): 2-pin 12V socket	15
55	Left front lamp unit (Bi-xenon) Right front lamp unit (Bi-xenon)	7.5
55	Left front lamp unit (Hi-xenon)	10
56	Spare	10
56	Right front lamp unit (Hi-xenon)	10
57	2009-2011: Trailer hitch socket (13-pin)	15
57	2005-2008: Audio gateway control unit (Japan)	25
57	2005-2008: SDAR control unit Emergency call system control unit (USA)	7.5
58	Trailer control unit	25
59	Trailer control unit (vehicles up to 31.5.05) Trailer hitch socket (13-pin) (vehicles as of 1.6.05)	20
60	Driver seat connector block	20
61	Front passenger seat connector block	20
62	Circuit 15 relay (2) (SA: xenon, cell phone)	25
63	Spare (vehicles up to 31.5.05)	–
63	Valid for government vehicles (2009-2011): Roof light bar	25
63	Emergency call system control unit (USA) (vehicles as of 1.6.05) SDAR control unit (vehicles as of 1.6.05)	7.5
64	Valid for engine 266: Air pump relay	40
64	Valid for engine 640: Engine wiring harness/engine compartment connector (2005-2008), Glow time output stage (2009-2011)	80
65	Electric power steering (ES) control unit	80
66	SAM control unit	60
67	Circuit 15R relay (2) (SE)	50
68	Valid for engine 266.920 and engine 266.940 with transmission 722: AAC with integrated control additional fan motor	50
68	Valid for engine 640.940, 640.941, 266.960, 266.980 and for engine 266.920, 266.940 with (Trailer hitch): AAC with integrated control additional fan motor	60
69	Circuit 15R relay (1)	50
70	Circuit 15 relay (1)	60
71	Valid for engine 640: PTC heater booster	150
72	2005-2008: Circuit 30 connector sleeve 2009-2011: Special vehicle multifunction control unit (SVMCU [MSS]) (Taxi) Valid for government vehicles: Fuse 7 Fuse 10	60

Relay Panel (K100)

Fuse box location

Fuse box diagram

Relay Panel (K100)

№	Fused function	Amp
80	Reserved for special-purpose vehicles	30
81	Reserved for special-purpose vehicles	30
82	Reserved for special-purpose vehicles	30
83	Reserved for special-purpose vehicles	30

	Relay
A	Circuit 15R relay (2) (SA)
B	Circuit 15R relay (1)
C	Fanfare horn relay
D	Heated rear window relay
E	Wiper stage 1/2 relay
F	Wiper ON/OFF relay
G	Circuit 15 relay (1)
H	Backup relay
I	Valid for engine 266: Air pump relay
K	Fuel pump relay
L	Engine circuit 87 relay
M	Starter relay
N	Circuit 87F relay
O	Circuit 15 relay (2) (SA: xenon, cell phone)