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Hello guys,

I have a 2002 3 door 1.4 Civic, key sign flashing, car doesn't start.
In immo I have dtc: "No communication between imoes unit and immobilizer unit". Imoes unit in this car is the micu.
I have checked wiring from immo to micu and from micu to engine control unit. All good, checked signal with oscilloscope, nice, undisturbed signal.
I tried to make a replace a MPCS/MICU/IMOES with diag tool to match them together, but doesn't let me, it shows a message "immobilizer is not normal". Keys are recognized.
Can the micu be the problem? (Part nr.: 3820A-S6A-G101)
I can't think of anything else.
Is it a plug and play if I buy a used one? I read it is, but if it is a plug and play why is there a function in hds "Replace MPCS/MICU/IMOES"?
Thank you in advance
Kalman

 
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Could someone provide me a service manual, or wiring diagram for 2001-2005 civic ?
Thanks in advance

 
Rep Power: 518

I would venture some guesses but our cars in N.A. aren't exactly the same as yours on that side of the pond and I have no good info on your models.
Over here the MICU on 01-05 (7th gen here, and used immobi type 3) does not contain an integral part of the immobilizer system; the IMOES was first included in 06 (8th gen here and used immobi type 6) for our Civics over here and that unit lives in the fusebox (MICU) on those cars.

Service manuals;
Click this link, go to the very last page of the thread (it's like 10 or more pages deep), most recent links are back there. Most seemed to cover many cars worldwide, so be careful to choose and verify the info applies to your specific version of the car

LINKY CLICK: civicforums.com/ 7th-gen-manual-free-updated.html

 
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Thanks ezone, I opened the Micu, which the IMOCD line (one wire immo-pcm communication line) goes through and checked where the lines run inside.
It is clearly ment for communication back and forth. There is a transistor, that can pull it down to earth answer, and it is also connected to one of the i/o ports through a resistor of the mcu to listen.
I replace it tomorrow, and get back with the results.

 
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Thanks to everyone, it was the fusebox (micu) that had to be replaced and had to be registered to the immo with hds.