My car developed a few electrical issues one of which is the immobiliser is not recognising the key. To drive the car I had to remove the immobiliser EEPROM (IC: L56R-93c56) on the ECU. The car drives fine but the engine management light is ON as well as there is a fault code P1607. Therefore I fitted a salvaged MICU and all the systems that did not work before work fine now apart from remote central locking (as immo EEPROM is missing) and green key flashing. I intended to solder back the original EEPROM however it got damaged either in storage or during unsoldering. Now my question is there a way to program immo EEPROM using code stored in keys? Or is there a “virgin” hex load that could be used to initialise syncing between ECU, immo and keys? Another worrying fact is that when I opened the old faulty MICU I noticed IC: IS93C46-3 1024-bit memory. I was under impression that in the 7th generation, Civic MICU is not serialised could anyone confirm? Additionally, I never paid attention to the fact that my old MICU R1 relay is missing. I believe it operates the magnetic clutch of the AC unit during the startup. Could anyone shine more light on its function?
There is no virgin file for these floating around so you would have to buy a virgin ecu to copy it from. There is no point tho cause you'd still have to program it same as if using a used file.
Use this file on a new 93C56 eeprom for your ecu : https://autoelectronics101.com/tmp/civicl56ecudump.zip
After, you will need to use a diagnostic tool like Autel or dealers iHDS to run the "immobilizer/ecu/micu replacement" function. After that your ecu/micu/keys will all be synced and immo system will be back to normal with out the rom errors from ECU like your getting now with no eeprom installed.
The micu is part of the immobilizer chain so replacing it requires re-programming the immobilizer system same way I described above for the ECU. The relay missing in your micu is probably normal. They used the same pcb for different models. Your car probably just did not have what ever the function of what that relay controlled so it was not populated for boards with your part number. If your replacement has it then that means its not the correct part and may or may not have DTC's related to the added functions that are not present.