[wolfman66]

Hallo yesterday my car stop at the road.And problem was the fuse for ecu 4.And I replaces the 20 amp fuse,then the motor start again..
My question is what it is ECU 4?

[tw2005]

Hallo yesterday my car stop at the road.And problem was the fuse for ecu 4.And I replaces the 20 amp fuse,then the motor start again..
My question is what it is ECU 4?

Believe it or not it's a 20Amp fuse to the ECU.  Signal goes to the main relay, latches then power is applied to the ECU via the 20amp fuse.

Same relay also supplies power elsewhere as well via other fuses

I'm not 100% sure I understand what you're asking

Are you asking what is ECU for? ECU is the Engine Control Unit...the cars brain

[wolfman66]

Theres is 4 fuse in row which is say ecu 1,2,3 and 4..But I wonder what is ecu 4 goes to for an application in the car?..I why did  the fuse popping,is that groundproblem or bad connection with some connetor?

They're not very descriptive of what they are actually for, my model has engine icon pictures rather than ECU text on 11 fuses, couldn't say which one does what