BMW E87 E90 116i 316i Petrol N45 Wire Wiring Harness Engine Gearbox Mod Loom

BMW E87 E90 116i 316i Petrol N45 Wire Wiring Harness Engine Gearbox Mod Loom is an original electrical harness from the Wires, harnesses and connectors group, designed for N45 petrol units in 1 and 3 series models. The component ensures a proper electrical connection between the engine and the gearbox, which translates into stable operation of control systems and reliable module communication.

Specifications and technical data

• SKU: 7545165
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 7545165
• Substitutable numbers: 12517549258, 7549258, 12517545165 12517549256 12537540710, 7545165 7549256 7540710
• Fuel type: Petrol
• Category: Wiring Harnesses, Cables & Connectors

Purpose and function of the harness

The presented wiring harness has been designed specifically for BMW powertrains with the N45 petrol engine in 116i and 316i versions. It is responsible for distributing signals and power between sensors, engine actuators, and components related to the gearbox. As a result, the engine control unit can consistently control the operation of the powertrain, and the gearbox receives the correct information for smooth gear shifting.

The harness is a key element of the engine bay's electrical infrastructure – its correct selection in terms of fuel type, engine generation, and specific BMW model configuration allows for avoiding problems with starting, CAN communication errors, or unstable operation of accessories.

Construction and technical compatibility

As an element from the Wires, harnesses and connectors group, the product includes a set of wires with factory connectors matched to the sockets in the engine and gearbox. The connectors used are prepared for operation in the demanding environment of the engine bay, where variable temperatures, vibrations, and moisture occur. The appropriate geometry of the harness allows it to be routed according to factory paths, which minimizes the risk of abrasion and mechanical damage.

The original BMW solution ensures the proper placement of mounting points, wire segment lengths, and connector configuration consistent with factory electrical diagrams. Thanks to this, the harness works with the petrol engine control system, maintaining the parameters specified by the vehicle manufacturer.

Application in the N45 petrol engine

The N45 engine is a petrol unit in which correct wiring has a direct impact on the operation of ignition, injection, and auxiliary systems. The described wiring harness handles signals from position, temperature, or pressure sensors and supplies power to actuators such as ignition coils or control valves. Proper electrical integrity of the harness reduces interference and voltage drops, which promotes stable operation of the petrol unit.

Selecting a harness dedicated to a specific fuel type is important from the point of view of compatibility with ECU maps and accessory configuration. In the case of BMW petrol engines, using the appropriate harness translates into the correct operation of diagnostic systems and easier identification of potential faults.

Condition, installation, and benefits of use

The item comes from dismantling and is offered as a used part, which allows for an economical repair of the electrical installation in BMW 1 and 3 series with the N45 engine. Replacing a damaged or burnt harness with an original component of this type is often the fastest way to restore full functionality of the powertrain without the need for time-consuming repairs of individual wires.

Using a factory wiring harness ensures:

• compliance with BMW factory electrical diagrams,
• matching of connectors to engine and gearbox accessories,
• organized routing of wires in the engine bay,
• reduction of the risk of communication errors and starting problems.

Expansion of the BMW electrical system

If you are planning a comprehensive repair or upgrade of the engine area in your BMW and need other elements from the same group, such as additional harnesses, signal wires, or service connectors, check the available parts in the BMW Wires, harnesses and connectors category.

For a comparison of solutions used in the premium segment and a better understanding of the advantages of original components from dismantling, you can read an article describing the topic of used components in high-class vehicles: used parts for Mercedes – original components from dismantling.