I missed a track day last weekend because of this issue. The car ran great on Saturday, but wouldn't start on Sunday. The immobi light comes on and blinks continuously.

The first thing I did was remove my V-AFC's harness in case it was bad, but nothing chanced.

I then followed all the troubleshooting steps starting on page 22-120 of the service manual. Everything passed: the ECU reports no codes, there is battery voltage at pin 1 of the immobi receiver, ground at pin 4, and continuity between pins 2 and 3 and their respective ECU pins. I also checked that pins 2 and 3 were not shorted to ground and that they made good contact with the male portion of the harness (by checking for continuity with my V-AFC's harness).

So I ordered a used key cylinder with immobi attached. I pulled the immobi off the cylinder and tried it with my original key. No change.

The car had this issue once before when I had the dash all taken apart. Plugging the dash back in seemed to fix it so I didn't think anything of it.

At this point I'm thinking the ECU is dead. If it is I'm going with a standalone. Has anyone had an ECU die like this? Is there anything left to check? The only thing I can think of is to have the ECU reprogrammed by Honda (I don't want to know what they'll charge for this) or checking the key code at the ECU with an oscilloscope.

Thanks for any help.

 

take the cover off the ecu and break the immobilizer control board out of the ecu.

you will have a cel for internal ecu circuit failure but the car will run fine.

If you post a pic of the inside i can tell you which one it is.

you can even swap those boards between ecu's so you dont have to get the crap reset at the dealer

 

Aha - thanks! I found a pic on another Honda board and pulled the thing out (its the only other PCB soldered to the main board). Car started up fine. I haven't read codes but its a race car and throws a few anyways.

This will let me get rid of some more wiring too.

 

Anyone have a picture/diagram of the chip that needs to be removed from the ECU to disable to immobilizer? I have no electronic prowess and would really appreciated the help since my car refuses to start and the dealers in Thailand are completely unprepared to service my car.

Thanks,
Nathan