Greetings all, first time poster. Recently purchased a very good condition 2000 Honda Accord EX V6. Runs great but has occasional starting problems that I think are due to the immobilizer system. Been searching around but haven't come up with a solution yet.

When turning to the ON position without actually cranking the car, I will occasionally get a solid green light, and occasionally get no green light at all. The presence of the green light determines whether or not the car will start. When I do get the green light, car starts no problem, and when I turn off and remove the key, the green light flashes at me 5 times. If there is no green light, the car will crank but not start. I have 2 separate factory keys that have shown these symptoms. I also have a non-factory key that looks like it was cut at home depot, and when I attempt to use that in the ignition, it gives me the flashing green key light when turned to the on position.

When searching about this problem on the web, most of the problems people encounter are with the flashing green key light, suggesting the immobilizer system does not recognize the key. I haven't come across my specific problem where the green key light occasionally comes on and occasionally doesn't. I've checked the fuses on the driver's side and under the hood and both are fine. What should be my next move?

Thanks in advance.

 

After finding this video:


I tried replacing the Main relay with a Honda OEM part and so far it seems to be working out. Will report back if it is not the solution, but so far seems to be working.