Automotive power system control wiring harnesses

The control wiring harness of the automotive power system is the core part of the entire vehicle's electrical system, responsible for connecting key components such as the controller, sensors, and actuators of the power system, ensuring the efficiency and reliability of power transmission, energy management, and system coordination. Its design directly affects vehicle performance, fuel economy, emission control and driving experience

The control wiring harness of the automotive power system is the core part of the entire vehicle's electrical system, responsible for connecting key components such as the controller, sensors, and actuators of the power system, ensuring the efficiency and reliability of power transmission, energy management, and system coordination. Its design directly affects vehicle performance, fuel economy, emission control and driving experience. The following is a detailed description of the power system control wiring harness:

Depending on the type of power system (fuel vehicle, hybrid, pure electric), the composition of the wiring harness varies slightly, but the core functional modules are as follows:

1.Engine control wiring harness (Fuel vehicle/Hybrid)

Function: Connect the engine control unit (ECU) with sensors and actuators to achieve fuel injection, ignition, emission control, etc.

Composition:

◎.Sensor wiring harness

  1.1.Crankshaft position sensor, camshaft position sensor: Monitor engine speed and phase.

  1.2.Oxygen sensor (front/rear oxygen) : Detects the oxygen content in the exhaust gas and optimizes the air-fuel ratio.

  1.3.Knock sensor: Prevents engine knocking and adjusts ignition timing.

  1.4.Intake pressure/temperature sensor: Calculates the intake volume and optimizes combustion efficiency.

◎.Actuator wiring harness

  1.5.Fuel injector wiring harness: Controls the amount and timing of fuel injection.

  1.6.Ignition coil wiring harness: Transmits ignition signals and drives the spark plug to ignite.

  1.7.Throttle control wiring harness: Adjust the throttle opening to control the intake air volume.

2. Transmission control wiring harness

Function: Connect to the transmission control module (TCU) to optimize the shift logic and transmission efficiency.

Composition:

◎.Input/Output shaft speed sensor: Monitors the input and output speeds of the transmission and calculates the timing of gear shifting.

◎.Oil temperature/pressure sensor: Protects the transmission from overload or high-temperature damage.

◎.Solenoid valve wiring harness: Controls the hydraulic oil circuit to achieve clutch engagement and gear shifting (such as in AT and DCT transmissions).

3. Motor control wiring harness (for new energy vehicles)

Function: Connect the motor controller (MCU), drive the motor and the energy management system.

Composition:

◎.Motor rotary transformer wiring harness: Detects the position and speed of the motor rotor (for permanent magnet synchronous motors).

◎.Temperature sensor wiring harness: Monitor the temperature of the motor windings to prevent overheating.

◎.Three-phase AC wiring harness (high voltage) : Transmits the electrical energy driven by the motor (requires shielding design to reduce electromagnetic interference).

4. Battery Management System (BMS) Wiring Harness (for new energy vehicles)

Function: Monitor the status of power batteries to ensure safety and lifespan.

Composition:

◎.Single-cell voltage/temperature acquisition wiring harness: The voltage and temperature sensors connected to each battery cell.

◎.Total voltage/total current detection wiring harness: Measures the total voltage of the battery pack and the charging and discharging current.

◎.Balancing control wiring harness: Through active/passive balancing circuits, it balances the voltage differences between battery cells.

5. Energy recovery and braking system wiring harness

Function: Coordinate the switching between braking energy recovery and mechanical braking (for new energy vehicles).

Composition:

◎.Brake pedal sensor wiring harness: Detects the pedal travel and calculates the energy recovery intensity.

◎.Regenerative braking control wiring harness: Connects the motor controller to the braking control unit (EBCM).

 

Typical application cases

1.Traditional fuel vehicles (such as the Volkswagen EA888 engine)

The wiring harness integrates oxygen sensors, turbocharging pressure sensors, and direct injection injectors, supporting high-precision fuel layer-by-layer injection and turbine control.

2. Hybrid models (such as Toyota's THS system)

The power distribution unit (PSD) control wiring harness connects the ECU and MG1/MG2 motors to achieve power splitting between the engine and the motors.

3. Pure electric vehicles (such as Tesla Model 3)

The motor control wiring harness adopts multi-layer shielding and supports an instantaneous current of up to 1000A. The BMS wiring harness enables real-time monitoring of thousands of battery cells.  

The power system control wiring harness is the neural network between the "heart" and the "brain" of a vehicle, and its design needs to strike a balance among performance, safety and cost. With the deepening of electrification and intelligence technologies, power system wiring harnesses will face challenges such as higher power density, more stringent EMC requirements, and higher integration. However, the core mission remains to accurately and reliably transmit energy and signals