The Engine Control Unit (ECU) is installed in the vehicle. To ensure the ECU operates reliably and normally, the installation and usage requirements for the ECU are as follows:
1. ECU Operating Environment Temperature Requirements
Operating temperature range: -40℃ to +105℃;
1) If the temperature exceeds this range, cooling measures should be implemented. Ensure the ECU is placed in a location with good air circulation;
2) Avoid sudden temperature changes;
3) Prevent accumulation of dirt (mud, dust, oil, etc.) on the ECU surface, as this will significantly impair the ECU’s heat dissipation capability.
2. ECU Vibration Requirements:
1) The vibrations considered during the ECU design are shown in the table below. Any vibrations exceeding the design conditions are not permitted.
Random vibration spectrum:
Harmonic spectrum (Note: g is acceleration)
2) During normal operation, the vibration frequency of the ECU should be less than 500Hz;
3) Use a four-point symmetrical installation, and decide whether to add vibration-damping pads based on specific conditions (the ECU is shipped with pads; do not remove them), while ensuring a secure installation to prevent detachment;
4) The ECU should not be directly connected to the vehicle; it is recommended to use a flat plate as a transition;
5) The wiring harness should be securely installed before entering the ECU to avoid transmitting vibrations to the ECU.
3. ECU Installation Location Requirements:
1) Ensure good ventilation; do not cover the ECU to prevent dust accumulation over time; otherwise, it will affect the ECU’s heat dissipation;
2) Keep away from heat sources (such as exhaust pipes, catalytic converters, etc.) to avoid thermal radiation on the ECU; prevent heat flow from heat sources from directly affecting the ECU;
3) Stay away from high-frequency, high-energy sound sources, such as generators, oil pumps, water pumps, air pumps, etc.;
4) Choose a relatively high and dry location to avoid prolonged exposure to moisture, prevent water immersion, avoid mud splashes and stone impacts during driving; prevent corrosive liquids from contacting the ECU and control wiring harness;
5) The wiring harness near the ECU must be securely fixed to prevent disconnection or breakage;
6) Consider adding protective covers or other forms of protection as needed;
7) Do not install on areas with high vibrations, such as cargo panels or beams;
8) Ensure the ECU is properly grounded;
9) Ensure there are no strong electromagnetic sources nearby to guarantee electromagnetic shielding;
10) Installation and maintenance should be convenient.
4. ECU Installation Direction Requirements:
1) Vertical installation is required; refer to the installation direction shown in Figure 1, and try to use an installation method with an appropriate angle at the top to avoid oil, water, etc., from pooling on the ECU surface;
2) The wiring harness should enter from the bottom of the ECU. If this cannot be ensured, it can enter from the side of the ECU;
3) The wiring harness should not enter from the top of the ECU.
ECU Installation Direction Diagram
5. ECU Grounding Requirements:
Poor grounding can lead to electromagnetic compatibility issues and other related problems, such as distortion of crankshaft and camshaft signals during engine startup.
The following are grounding precautions:
1) Connect the negative terminal of the battery to the negative terminal of the starter;
2) Connect the negative terminal of the starter to the engine body;
3) Connect the controller housing ground wire to the chassis to ensure good grounding of the controller housing;
4) Connect the engine body to the 0V of the instrument mainboard;
5) Connect all loads and controller ground terminals to the 0V of the instrument mainboard;
6) Avoid directly connecting the ECU to the negative terminal of the battery.
Grounding Diagram