Mercedes-Benz A-Class Fuse Box Locations and Diagrams (2004-2012)

The second-generation Mercedes-Benz A-Class (W169), produced from 2004 to 2012, built upon the unique design of its predecessor while refining the compact MPV concept. With a focus on improved interior space, safety, and driving dynamics, the W169 offered a range of efficient engines and advanced features for its class. Its tall, upright stance combined with Mercedes-Benz engineering made it a practical yet premium choice for urban drivers and small families alike.

In this article, you will find fuse box diagrams for the Mercedes-Benz A-Class, covering models A150, A160, A180, and A200 for the years 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, and 2012. These diagrams offer critical insights into the fuse layout, making it easier to locate, identify, and understand the role of each fuse and relay in your vehicle’s electrical system.

What’s Included:

Fuse Box Diagrams – Clear and labeled illustrations to help pinpoint specific fuses, relays, and circuit breakers.
Fuse Panel Locations – Step-by-step directions on where to find fuse panels inside the vehicle, including the dashboard and engine bay areas.
Fuse Assignments – Detailed descriptions of each fuse and relay function to support accurate troubleshooting and electrical repair.

Whether you’re troubleshooting an electrical issue, replacing a blown fuse, or performing regular maintenance, this guide provides everything you need to keep your Mercedes-Benz A-Class (2004–2012) running smoothly.

Maintain peak reliability and performance with this complete fuse box, fuse panel, and relay diagram guide for the W169 A-Class.

The cigar lighter (power outlet) fuses in the Mercedes-Benz A-Class are located in the Passenger Compartment Fuse Box:
- Fuse №38: Front Cigar Lighter
- Fuse №52: 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 A-Class (W169; 2005-2012)

Fuse box diagram

Assignment of the fuses in the passenger compartment

№	Fused function	Amp
1	Stop light switch	10
1	Valid for code (U62) Light and vision package: 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	Valid without code (580) Automatic air conditioning and without code (581) Comfort automatic air conditioning: HEAT control and operating unit Valid for code (580) Automatic air conditioning: AAC [KLA] control and operating unit Valid for code (581) 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
7	Valid for model 169.090: DC/DC converter control unit	5
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	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 PTS control unit	10
17	Rotary light switch	5
18	Valid for transmission 711, 716: Backup lamp switch Valid for model 169.090: A/C compressor control unit BKGN Energy monitoring control unit Vacuum pump 1 control unit Vacuum pump 2 control unit	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	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	Central gateway control unit (vehicles up to 30.11.05) Rotary light switch Automatic light switch daylight sensor Rain/light sensor	5
32	Valid for engine 266: ME-SFI [ME] control unit Valid for model 169.090: Energy monitoring 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	Cell phone separation point Trailer control unit	7.5
36	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	Overhead control panel control unit	7.5
40	Roof motor	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	15
43	Valid for engine 640: Terminal 87M1e connector sleeve	7.5
43	Valid for model 169.090: Vacuum pump 1 control unit	20
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 Valid for model 169.090: Vacuum pump 2 control unit	25
46	Telephone control unit, (Japan) E-net compensator Universal Portable CTeL Interface (UPCI [UHI]) control unit	7.5
46	Bass module speaker (Japan)	25
46	Amplifier for sound system	40
46	Valid for model 169.090: Charging control unit	5
47	Telephone control unit, (Japan) Universal Portable CTEL Interface (UPCI [UHI]) control unit Cell phone separation point Voice control system (VCS [SBS]) control unit Valid for model 169.090: Charger 1	7.5
48	ATA [EDW]/tow-away protection/interior protection control unit Alarm signal horn with additional battery Valid for model 169.090: Charger 2	7.5
49	Upper control panel control unit Left front seat heated cushion Left front backrest heated cushion Right front seat cushion heater element Right front backrest seat cushion heater element	25
50	CD changer Media interface control unit Digital TV tuner Digital Audio Broadcasting control unit VICS+ETC voltage supply separation point (Japan)	7.5
50	Valid for government vehicles: Roof light bar, Circuit 30 connector sleeve	30
51	Valid for model 169.090: Cooling fan, Low temperature coolant pump	10
52	VICS+ETC voltage supply separation point (Japan) (vehicles up to 31.5.06) Valid for model 169.090: Electric drive control unit	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 model 169.090: Electric drive control unit	5
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	Trailer hitch socket (13-pin) (vehicles as of 1.6.05)	15
57	Audio gateway control unit (Japan) (vehicles up to 31.5.05)	25
57	SDAR control unit Emergency call system control unit (USA)	7.5
58	Trailer control unit Valid for model 169.090: Vehicle gateway 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
59	Valid for model 169.090: Battery management system control unit 1	5
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	Audio gateway control unit (Japan) (vehicles as of 1.6.05) Valid for government vehicles: Roof light bar	25
63	Emergency call system control unit (USA) (vehicles as of 1.6.05) SDAR control unit	7.5
63	Valid for model 169.090: Battery management system control unit 2	5
64	Valid for engine 266: Air pump relay	40
64	Valid for engine 640: Engine wiring harness/engine compartment connector, Glow time output stage	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	Circuit 30 connector sleeve Special vehicle multifunction control unit (SVMCU [MSS]) (Taxi)	60

Relay Panel (K100)

Fuse box location

Relay Panel location (K100): Mercedes-Benz A-Class (2005-2012)

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	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)