The BMW 3-Series, specifically the E90, E91, E92, and E93 models produced between 2005 and 2010, is a highly popular and well-regarded luxury compact car range. Known for its dynamic driving experience, refined design, and cutting-edge technology, the 3-Series has captured the hearts of car enthusiasts worldwide. The beginning of the production of the sedan e90 – 2005. The station wagon (E91), coupe (E92), and convertible (E93) went into production at the end of 2006.
In this comprehensive article, we will delve into the various electrical components of the BMW 3-Series (E90, E91, E92, E93) and explore the essential roles of the fuse box and relay systems in their electrical architecture.
Electrical Components in the BMW 3-Series (E90, E91, E92, E93)
The BMW 3-Series (E90, E91, E92, E93) encompasses an array of sophisticated electrical components that contribute to its advanced functionality and performance. Among these components, the fuse box and relay systems play vital roles in ensuring the proper distribution and protection of electrical power throughout the vehicle.
Fuse Box System
The fuse box in the BMW 3-Series (E90, E91, E92, E93) is a critical component responsible for protecting the car’s electrical circuits from overloading or short circuits. Located in various positions within the vehicle, such as the glove compartment, engine compartment, or trunk, the fuse box houses a series of fuses that are designed to blow and interrupt the electrical circuit in case of a fault.
The fuses in the BMW 3-Series are typically color-coded to indicate their amperage rating and protect specific electrical functions. A blown fuse can be easily identified by a visible break in the metal strip inside the fuse. If an electrical components malfunctions, such as the headlights or audio system, checking the fuse box for a blown fuse is an essential troubleshooting step. The fuse box diagram, often found on the fuse box cover or in the owner’s manual, provides a map of the fuse positions and their corresponding electrical functions.
Relay System
The relay system in the BMW 3-Series (E90, E91, E92, E93) works in conjunction with the fuse box to control the flow of electrical power to various components and systems. Relays are electromagnetic switches that activate or deactivate the circuit they are associated with. They serve as intermediaries between the electrical switches and the actual electrical components, ensuring the correct operation and coordination of various functions.
Relays in the BMW 3-Series can be found in different locations, depending on the specific model and component. Common relays include those for the fuel pump, radiator fan, headlights, and wipers. A malfunctioning relay can lead to the failure of the associated electrical component. If a specific system or component stops working, checking the relay related to that function can help identify the issue. The relay diagram, usually located in the fuse box cover or owner’s manual, provides information on the location and purpose of each relay.
(2005-2010) BMW 3-Series (E90, E91, E92, E93) fuse box and relay with Diagram
WARNING
- Never replace a fuse with one that has a higher amperage rating.
- A fuse with a too-high amperage could damage the electrical part and cause a fire.
- On no account should fuses be repaired (e.g. patched up with tin foil or wire) as this may cause serious damage elsewhere in the electrical circuit or cause a fire.
- If a fuse blows repeatedly, do not keep replacing it. Instead, have the cause for the repeated short circuit or overload tracked and fixed.
BMW 3-Series (E90, E91, E92, E93) 2005-2010 fuse assignment
Fuse box locations
- Rear power distribution panel (high amperage fuses)
- Junction box fuse panel (←-03.2007 / 03.2007-09.2007 / 09.2007-→)
- E-box engine electronics fuse carriers
Behind glove compartment (to 03.2007)
| No. | Amps | Assignment/Designation |
| F1 | — | — |
| F2 | 5A | Diversity antenna |
| F3 | 20A | Passenger seat heating |
| F4 | 5A | Car access system |
| F5 | 7.5A | Roof function control center |
| F6 | 15A | Transmission control module |
| F7 | 20A | Auxiliary heater control module |
| F8 | 5A | CD changer Diversity antenna |
| F9 | 10A | Active cruise control |
| F10 | — | — |
| F11 | 10A | Radio |
| F12 | 20A | Convertible top or sunroof control Roof function center (FZD) |
| F13 | 5A | iDrive controller |
| F14 | — | — |
| F15 | 5A | AUC sensor |
| F16 | 15A | Horns |
| F17 | 5A | Telephone eject box Telephone transceiver |
| F18 | 5A | CD changer |
| F19 | 7.5A | Comfort access control module Front door outer handles control modules Siren and tilt alarm sensor |
| F20 | 5A | DSC Transfer case control module |
| F21 | 7.5A | Driver door switch cluster Outside rear view mirrors |
| F22 | 10A | Longitudinal dynamics management Towing hitch release speaker |
| F23 | 10A | Digital tuner Satellite radio |
| F24 | 5A | Tire pressure control (RDC) |
| F25 | 10A | Front seat belts positioner control modules |
| F26 | 10A | Shift selector lighting Telephone eject box Telephone transceiver |
| F27 | 5A | Driver door switch cluster Telephone transceiver |
| F28 | 5A | Roof function control center Park distance control (PDC) |
| F29 | 5A | AUC sensor Front seat heating modules |
| F30 | 20A | 12-volt utility sockets Front cigar lighter |
| F31 | 20A | CCC/M-ASK Radio |
| F32 | 30A | Driver seat heating module Driver seat module |
| F33 | 30A | Front seat control |
| F34 | 30A | Sound system amplifier |
| F35 | 30A | DSC |
| F36 | 30A | Footwell module |
| F37 | 30A | Driver seat control |
| F38 | 30A | Transfer case control module |
| F39 | 30A | Wipers |
| F40 | 20A | Fuel pump (EKPS) |
| F41 | 30A | Footwell module |
| F42 | 30A | Trailer module |
| F43 | 30A | Headlight washer pump |
| F44 | 30A | Trailer module |
| F45 | 40A | Active steering |
| F46 | 30A | Rear window defroster |
| F47 | 20A | Trailer socket |
| F48 | 20A | Rear wiper and washer control |
| F49 | 30A | Passenger seat heating |
| F50 | 40A | Active steering |
| F51 | 50A | Car access system |
| F52 | 50A | Footwell module |
| F53 | 50A | Footwell module |
| F54 | 60A | B+ potential distributor |
| F55 | — | — |
| F56 | 15A | Central locking |
| F57 | 15A | Central locking |
| F58 | 5A | Instrument cluster OBD II socket |
| F59 | 5A | Steering column switch cluster |
| F60 | 7.5A | A/C and heating system |
| F61 | 10A | Cargo compartment lights Central information display Glove compartment light Trunk light |
| F62 | 30A | Window control |
| F63 | 30A | Window control |
| F64 | 30A | Window control |
| F65 | 40A | DSC |
| F66 | 50A | Fuel heater (Diesel) |
| F67 | 50A | Blower output stage |
| F68 | 50A | Vacuum pump relay |
| F69 | 50A | Engine cooling fan |
| F70 | 50A | Secondary air injection pump |
| F71 | 20A | Trailer socket |
| F72 | — | — |
| F73 | — | — |
| F74 | — | — |
| F75 | — | — |
| F76 | — | — |
| F77 | 30A | Fuel injectors Ignition coils Interference suppression capacitor |
| F78 | — | — |
| F79 | — | — |
| F80 | — | — |
| F81 | — | — |
| F82 | — | — |
| F83 | — | — |
| F84 | — | — |
| F85 | — | — |
| F86 | — | — |
| F87 | — | — |
| F88 | — | — |
- I01068 – Relay, terminal 30g
- I01069 – Relay, terminal 15 (on PC board)
- K2 – Horn relay (on PC board)
- K6 – Headlight washer relay
- K13 – Rear window defroster relay
- K36 – Wiper relay 1
- K37 – Wiper relay 2
- K91 – Rear wiper relay (Sports Wagon)
- K6304 – Secondary air injection pump relay
Behind glove compartment (03.2007 – 09.2007)
| No. | Amps | Assignment/Designation |
| F1 | 10A | Rollover protection control module |
| F2 | 5A | Instrument cluster OBD II plug |
| F3 | 20A | Passenger seat heating |
| F4 | 5A | Car access system |
| F5 | — | — |
| F6 | 15A | Transmission control module |
| F7 | 20A | Auxiliary heater control module |
| F8 | 20A | Sound system amplifier |
| F9 | 10A | Active cruise control |
| F10 | 15A | Trailer module |
| F11 | 10A | Radio |
| F12 | 20A | Convertible top or sunroof control Roof function center (FZD) |
| F13 | 5A | iDrive controller Tire pressure control (RDC) |
| F14 | — | — |
| F15 | 5A | AUC sensor |
| F16 | 15A | Horns |
| F17 | 5A | Telephone eject box Telephone transceiver |
| F18 | 5A | Convertible: Diversity antenna Gearshift bezel lighting Non-convertible: Electrochromic rearview mirror Gearshift bezel lighting |
| F19 | 7.5A | Siren and tilt alarm sensor |
| F20 | 5A | DSC Transfer case control module |
| F21 | 7.5A | Driver door switch cluster Outside rearview mirrors |
| F22 | 10A | Longitudinal dynamics management |
| F23 | 10A | Digital tuner Satellite Radio |
| F24 | 5A | DC converter Fan cutout relay |
| F25 | 10A | Front seat belts positioner control modules |
| F26 | 10A | Telephone eject box Telephone transceiver |
| F27 | 5A | Driver door switch cluster Telephone transceiver |
| F28 | 5A | Roof function control center Park distance control (PDC) |
| F29 | 5A | Front seat heating modules |
| F30 | 20A | 12-volt utility sockets Front cigar lighter |
| F31 | 20A | CCC/M-ASK |
| F32 | 30A | Driver seat module |
| F33 | 5A | Comfort access control module Front door outer handles control modules |
| F34 | 5A | CD changer Diversity antenna |
| F35 | 30A | DSC |
| F36 | 30A | Footwell module |
| F37 | 10A | Front seat control |
| F38 | 30A | Transfer case control module |
| F39 | 30A | Wipers |
| F40 | 7.5A | Roof function control center |
| F41 | 30A | Footwell module |
| F42 | 40A | Footwell module |
| F43 | — | — |
| F44 | 30A | Trailer module |
| F45 | 40A | Active steering |
| F46 | 30A | Rear window defroster |
| F47 | 20A | Trailer socket |
| F48 | 20A | Rear wiper and washer control |
| F49 | 30A | Passenger seat module |
| F50 | 10A | Engine control module (ECM) |
| F51 | 40A | Car access system |
| F52 | 20A | Driver seat heating |
| F53 | 20A | Passenger seat heating |
| F54 | 30A | Trailer module |
| F55 | — | — |
| F56 | 15A | Central locking |
| F57 | 15A | Central locking |
| F58 | 5A | Instrument cluster OBD II socket |
| F59 | 5A | Steering column switch cluster |
| F60 | 5A | Central information display |
| F61 | 10A | Cargo compartment lights Central information display Glove compartment light Trunk light |
| F62 | 30A | Window control |
| F63 | 30A | Window control |
| F64 | 30A | Window control |
| F65 | 10A | Selector lever illumination Longitudinal dynamics management |
| F66 | 50A | Fuel heater (Diesel) |
| F67 | 40A | Blower output stage |
| F68 | 40A | Footwell module |
| F69 | 50A | 400-watt engine cooling fan |
| 60A | 600-watt engine cooling fan | |
| F70 | 40A | Secondary air injection pump |
| F71 | 20A | Trailer socket |
| F72 | — | — |
| F73 | — | — |
| F74 | 10A | Engine control module (ECM) Exhaust flap Fuel tank leakage diagnostic module Nitrogen oxide sensor |
| F75 | 10A | EAC sensor E-box fan ECM Secondary air pump relay |
| F76 | 30A | Crankshaft sensor Fuel tank vent valve Mass airflow sensor Oil condition sensor Variable intake manifold controllers Volume control valve |
| F77 | 30A | Fuel injectors Ignition coils Ignition coil interference suppression capacitor |
| F78 | 30A | Camshaft sensors Coolant thermostat Electric coolant pump Engine control module (ECM) VANOS valves Waste gate valves |
| F79 | 30A | Crankcase breather heating Oxygen sensor heating |
| F80 | 40A | Non-turbo: Electric coolant pump |
| F81 | 30A | Trailer module |
| F82 | — | — |
| F83 | 40A | Footwell module |
| F84 | 30A | Headlight washer pump |
| F85 | — | — |
| F86 | — | — |
| F87 | — | — |
| F88 | 20A | Fuel pump (EKPS) |
- I01068 – Relay, terminal 30g
- K36 – Wiper relay 1
- K37 – Wiper relay 2
Behind glove compartment (09.2007-2010)
| No. | Amps | Assignment/Designation |
| F1 | 10A | Rear wiper and washer |
| F2 | 5A | Instrument cluster OBD II plug |
| F3 | 20A | Passenger seat heating |
| F4 | 10A | Engine control module (ECM)‘ |
| F5 | — | — |
| F6 | 5A | AUC sensor DC converter |
| F7 | 20A | Roof function center (FZD) Park distance control (PDC) |
| F8 | 20A | Cigar lighters Utility 12volt outlets |
| F9 | 5A | Driver door switch cluster Telephone |
| F10 | 5A | Front seat heating |
| F11 | 20A | Crankshaft sensor Engine control module (ECM) Fuel tank vent valve Fuel volume control valve Mass airflow sensor Oil condition sensor Variable intake manifold controllers |
| F12 | 15A | Vacuum pump relay |
| F13 | 5A | Telephone USB hub |
| F14 | 10A | Radio |
| F15 | 20A | Amplifier |
| F16 | 10A | EAC sensor E-box fan Engine control module (ECM) Radiator shutter control Secondary air pump relay |
| F17 | 10A | Engine control module (ECM) Exhaust flap Fuel tank leakage diagnostic module |
| F18 | 10A | Digital tuner Satellite Radio |
| F19 | 5A | CD changer Convertible: Diversity antenna |
| F20 | 10A | Seat control |
| F21 | 10A | Active cruise control |
| F22 | 15A | Automatic transmission control module |
| F23 | 20A | Auxiliary heater control |
| F24 | 15A | Towing module |
| F25 | 20A | Convertible top module Roof control center (FZD) |
| F26 | 5A | Dynamic stability control (DSC) Transfer case control module |
| F27 | 5A | iDrive controller Tire pressure control (RDC) |
| F28 | 5A | Cooling fan cut-out relay DC converter |
| F29 | 5A | Sunroof |
| F30 | 10A | Seat belt positioner controllers |
| F31 | 30A | Trailer module |
| F32 | 30A | Trailer module |
| F33 | 40A | Electric coolant pump |
| F34 | 5A | CD changer Diversity antenna |
| F35 | 30A | DSC |
| F36 | 40A | Car access system (CAS) |
| F37 | 30A | Camshaft sensors Coolant thermostat ECM Electric coolant pump VANOS valves Waste gate valves |
| F38 | 30A | Crankcase breather heating Engine control module (ECM) Oxygen sensor heating |
| F39 | 30A | Fuel injectors Ignition coils Ignition coil interference suppression capacitor |
| F40 | 30A | Transfer case control |
| F41 | 30A | Footwell module (FRM) |
| F42 | 40A | Footwell module |
| F43 | 30A | Headlight washer pump |
| F44 | 30A | Trailer module |
| F45 | 30A | Passenger seat module |
| F46 | 30A | Driver seat module |
| F47 | 30A | Rear window defogger |
| F48 | 30A | Headlight washer Rear wiper and washer control |
| F49 | 40A | Passenger seat module |
| F50 | 30A | Wiper control |
| F51 | 40A | Car access system |
| F52 | — | — |
| F53 | 10A | Rollover protection |
| F54 | 7.5A | Anti-theft alarm siren, tilt sensor Convertible: Door microwave sensors |
| F55 | 5A | Car access system (CAS) |
| F56 | 20A | CCC/M-ASK |
| F57 | 15A | Horns |
| F58 | 5A | Instrument cluster OBD II socket |
| F59 | 5A | Telephone |
| F60 | 5A | Central information display |
| F61 | 5A | Comfort access control module Dual remote control receiver Front door handle control module |
| F62 | 7.5A | Roof function control center (FZD) |
| F63 | 5A | Diversity antenna Electrochromic rear-view mirror Selector lever illumination |
| F64 | 5A | OBD II plug |
| F65 | 10A | Selector lever illumination Longitudinal dynamics management |
| F66 | 7.5A | Driver door switch cluster Passenger outside mirror |
| F67 | 20A | DSC |
| F68 | 20A | Driver seat heating module |
| F69 | — | — |
| F70 | 20A | Fuel pump (EKPS) |
| F71 | 20A | Trailer module |
| F72 | 15A | Central locking |
| F73 | 15A | Central locking |
| F74 | 5A | Instrument cluster |
| F75 | 5A | Passenger seat module |
| F76 | 5A | Radio |
| F77 | 10A | Glove compartment light Heating and air-conditioning Trunk or cargo compartment light |
| F78 | 30A | Window control |
| F79 | 30A | Wiper control |
| F80 | 30A | Window control |
| F81 | 30A | Footwell module |
| F82 | 30A | DSC control module |
| F83 | 40A | Footwell module |
| F84 | 40A | Footwell module |
| F85 | 30A | Car access system (CAS) |
| F86 | 40A | Footwell module |
| F87 | — | — |
| F88 | 40A | Blower |
| F89 | 40A | Secondary air pump relay |
| F90 | 40A | DSC control module |
| F91 | — | — |
| F92 | 50A | 400-watt engine cooling fan |
| 60A | 600-watt engine cooling fan |
- I01068 – Relay, terminal 30g
- K36 – Wiper relay 1
- K37 – Wiper relay 2
Rear power distribution panel
- Battery safety terminal (BST)
- Line to B+ junction, starter, and alternator
- Line to engine electronics
- Line to IBS electronics
- Line to junction box
- Battery sensor (IBS)
- Battery ground cable
- High amperage fuses (fusible links)
- Housing
- High current connector
- Battery
| No. | Amps | Assignment/Designation |
| to 03 / 2007 | ||
| F104 | — | Intelligent battery sensor (IBS) |
| F105 | 100A | Electronic power steering |
| F106 | 100A | Auxiliary heater |
| F106 | 100A | Electric auxiliary heater |
| F108 | 250A | Junction box |
| F203 | 100A | B+ terminal (engine compartment) |
| — | — | Starter, battery |
| from 03 / 2007 | ||
| F101 | 250A | Junction box |
| F102 | 100A | B+ terminal (engine compartment), starter, battery |
| F103 | 100A | Electronic power steering |
| F104 | 100A | Auxiliary heater |
| F105 | — | Intelligent battery sensor (IBS) |
| F106 | 100A | Electric auxiliary heater |
Engine electronics fuses (non-turbo to 03.2007)
- A6000 – Engine control module (ECM)
- K6300 – DME main relay
- K6319 – Valvetronic (VVT) relay
- K6327 – Fuel injector relay
- K6539 – Crankcase breather heating relay
| No. | Amps | Assignment/Designation |
| F01 | 30A | Ignition coils Interference suppression capacitor |
| F02 | 30A | Coolant thermostat Electric coolant pump Exhaust camshaft sensor Exhaust VANOS solenoid Intake camshaft sensor Intake VANOS solenoid |
| F03 | 20A | Crankshaft sensor Engine control module (ECM) Fuel tank vent valve Mass airflow sensor Oil condition sensor Variable intake manifold controllers |
| F04 | 30A | Crankcase breather heater Oxygen sensor heaters |
| F05 | 30A | Fuel injector relay |
| F06 | 10A | EAC sensor E-box fan Exhaust flap Fuel tank leakage diagnostic module Junction box Secondary air injection mass airflow sensor |
| F07 | 40A | Valvetronic (WT) relay |
| F09 | 30A | Electric coolant pump |
| F010 | 5A | Crankcase breather heating relay |
Engine electronics fuses (turbo from 03.2007)
| No. | Amps | Assignment/Designation |
| F01 | 30A | Ignition coils Interference suppression capacitor |
| F02 | 30A | Coolant thermostat Electric coolant pump Engine control module (ECM) Exhaust camshaft sensor Exhaust VANOS solenoid Intake camshaft sensor Intake VANOS sensor Wastegate valves |
| F03 | 20A | Crankshaft sensor Fuel tank vent valve Oil condition sensor Volume control valve |
| F04 | 30A | Crankcase breather heaters Oxygen sensor heaters |
| F05 | — | Not used |
| F06 | 10A | E-box fan Exhaust flap Fuel tank leakage diagnostic module |
| F07 | 40A | Electric coolant pump |
Engine electronics fuses (non-turbo to 03.2007)
- A6000 – Engine control module (ECM)
- K6319 – Valvetronic relay
- K9137 – Electric cooling fan cutoff relay
| No. | Amps | Assignment/Designation |
| F07 | 40A | Valvetronic (WT) relay |
Engine electronics fuses (turbo from 03.2007)
- A6000 – Engine control module (ECM)
- K9137 – Electric cooling fan cutoff relay
| No. | Amps | Assignment/Designation |
| F07 | 50A | Electric coolant pump |
Secondary air injection pump relay (2009-2010 non-turbo)
In conclusion, the BMW 3-Series (E90, E91, E92, E93) produced between 2005 and 2010 is a remarkable luxury compact car range renowned for its performance and advanced technology. Understanding the electrical components, such as the fuse box and relay systems, is crucial for troubleshooting electrical issues and maintaining the vehicle’s optimal functionality. Regular inspection and maintenance of the fuse box and relays, along with their respective diagrams and locations, can help ensure a reliable and enjoyable driving experience in the BMW 3-Series (E90, E91, E92, E93). Whether it’s diagnosing a malfunctioning electrical system or simply replacing a blown fuse, being familiar with the fuse box and relay diagrams and their locations can save time, effort, and potentially costly repairs.
The BMW 3-Series (E90, E91, E92, E93) fuse box and relay diagrams provide a clear overview of the electrical layout of the vehicle. They help identify the exact fuse or relay responsible for a specific function, making troubleshooting much more efficient. By referring to the diagrams, owners can quickly locate the fuse or relay they need to inspect or replace, eliminating guesswork and reducing the risk of damaging other components.
Additionally, the fuse box and relay diagrams can aid in understanding the electrical connections within the BMW 3-Series (E90, E91, E92, E93). This knowledge can be beneficial for enthusiasts and DIY enthusiasts who wish to undertake modifications or customizations to their vehicle’s electrical system. With the diagrams as a reference, they can ensure proper wiring and integration of new components without compromising the vehicle’s overall electrical integrity.
In summary, the fuse box and relay systems are integral components of the electrical architecture in the BMW 3-Series (E90, E91, E92, E93). The fuse box houses the fuses that protect various electrical circuits, while the relays control the flow of power to different components and systems. Understanding the fuse box and relay diagrams and their locations empowers owners to troubleshoot electrical issues effectively, maintain the vehicle’s optimal functionality, and even undertake electrical modifications with confidence. By leveraging these resources, BMW 3-Series (E90, E91, E92, E93) owners can ensure their vehicle’s electrical system operates smoothly and enjoy the driving experience this luxury compact car range has to offer.