Neighbors car.

2006 Hybrid, he drives it every other day, took off for work came back on a flat bed.
Came out to his car and it wouldn't start. AAA tried to boost jump start, nothing. Towed it home and the battery was reading 7.5V
Took it out and recharged the battery overnight. Unhooked it in the morning and by mid day it was still showing 12.6V. Battery is ~3years old.
Placed in car later that evening(still showing 12.6V), rotated key to ON and the green key light(immobilizer) kept blinking.

Tried the various tricks shown on YT and other forums and on here.
While battery was disconnected, battery leads were held together.
Reattched cables, did the windows closed, doors closed, LOCK/UNLOCK and attempt to start, still blinking key lamp.
Verified all appropriate fueses related to immobilizer and PCM were good.
We did not enter the code to the radio as we did not think this would have any effect on the starting of the vehicle.
[EDIT:] Forgot to mention, before inserting the key I hooked my OBDII code reader up to the cars OBDII port, and it started communicating with the PCM. This code reader requires car power to work, it is not self powered. It couldn't show data(engine run) but it was able to access any stored codes and communicate with the PCM. Which I thought was odd.Every other vehicle required the key to be inserted and ignition switched to ON. [/EDIT]


Questions I have.
Is it common/possible for the PCM to lose the keys programming if the 12V battery is disconnected? If so, does anyone know why? Both keys have been tried.
When the key is rotated from ON to START there is no activation of the starter. Is this normal when the immobilizer is active or is this indicative of another issue?
AFAIK the immobilizer kills the fuel and ignition system. It would make sense that the starter is also disabled but I haven't seen anyone saying/written this other than 'the car won't start'.
Can the PCM be reset to recognize the keys WITHOUT having to get raw dogged at the dealership? Can a mobile locksmith do it?

Thanks for any and all help.

 

Sounds like a ground issue. When you plug in a scanner, the scanner picks up ground and gives it to the ecu. Try starting the car with the scanner connected. And the immobilizer should only cut off the fuel pump if the key isn't detected after starting.

 

Thanks for the response.
I understand what you are saying but even if that was the case, should the OBDII scanner be able to handshake with the PCM with the ignition Locked/OFF and no key inserted?
These seems like something is real fucky.

Kinda thinking the ignition switch is toasted if this is the case. Contacts making/breaking when they shouldn't be. On another forum someone mentioned a stuck relay, but no mention of which relay to look at.

BTW, any idea of where a suspect ground might be?
I'm more of a '90-97 Accord guy, I know there a bunch of 'G' locations underhood/underdash, I'm assuming the Civic is the same?
Was thinking this after the fact but other things were kinda weird and it got late so I didn't do this exact procedure on its own.
That's what I thought. Should still be able to crank the engine, it just won't start as fuel is cut.
Did a voltage drop test, when turning to START there wasn't any voltage drop, besides from the initial drop when turning the key to ON. So that ruled out the starter circuit is being activated.

Thanks again.

And yes, I did look for an alarm system and didn't see anything under the dash, unless it was well done.

 

Some cars allow the scanner to work with the key in the ignition, some don't require it. Did you try starting the car with the scanner plugged in ? The main ground might be on the passenger side mount. Might be loose if work has been done recently. It usually takes atleast a couple hundred thousand miles for a Honda ignition switch to go bad. The engine should start but it'll just die afterwards when no key is detected. This assumes it's throwing a no-key detected light. Might wanna look in the ecu area and wiring areas where possible for any rodent chewings.

 

You never mentioned if it had any codes ? And you might be able to get the brake code from a dealer.

 

Hi Mike,

Did you every find a solution to this problem? I have the exact same issue for the same car. I am thinking to tow it to Honda and have them reprogram my keys. Do you think that would solve the issue???

Thank you!