Maximum amperage draw of an engine ECU, please?

[Yhoni]

Rectifier diode? Well, what kind of voltage source do you plan to use? If you plan to use a transformer, rectifier bridge and filter capacitor, you will also need to insert a voltage stabilizer (not necessarily to keep the voltage fixed, but to get rid of 50 Hz noise), or very large capacities for filtering.
If you do not connect anything to the ECU outputs (injectors, solenoid valves, induction coils ... etc.), the intensity of the absorbed current cannot be very high, regardless of the ECU. I would go for something of a 3-4 A, to ensure the charge of the capacitors from the internal sources of the ECU.

Hello friend, my power supply is a UNI-T up to 30v and 6A stabilized.

At the moment I am going to use the assembly to diagnose the ECUs by obd but I would also like to be able to check the outputs of the coils, injectors, etc ...

Thank you.