Hello everyone,I'm new here and i need some advice/help.
20 days ago i went on vacation,i came back yesterday and wanted to go somewhere but my key wouldn't turn at all,my brother told me it happend same day i left and he was able to start it 2-3 times,when he turns car off,the key wouldn't turn into on position or start car at all.
So today i went and bought new key ignition cylinder (whole steering wheel component) and replaced it,now the new key turns fine,but got new issue.
The car wont start,it cranks,and all lights are on,but it won't start.Checked it on OBD2 and it only shows P0420 code,which i have for over a year,and that's all i get.

So my question is,why it won't start?What could be the issue?
Fuel pump,starter,or something else???

I checked forum,but couldn't find the answer.
I'm not so good with cars and fixing them,but i do have "some" experience.
Could use some more help,thank you all.

The "green key light" in the gauges flashes angrily during and after cranking it?
This mess is not programmed to the car (Immobilizer).


Tow it to the dealer.



I could have rebuilt the old lock cylinder....too late now though.

What he said..

Think of it as the key "unlocking" the ECU..your new key doesnt unlock the ECU anymore.

Some locksmiths could do it for you, but may or may not be cheaper then the dealer.

It flashes before,during and after cranking it but not angrily,flashes normally just like it did before,when you leave key in the ignition.

Anything i can do to bypass it,or the only solution is to take it to dealer?

That light does not "flash normally" in a stock car that works correctly.
The only time it should flash is after you turn the ignition OFF it flashes 5 times then quits.

Does the car have a remote start or is there some other reason the immobilizer may have been bypassed?


A locksmith shop would have to be really well equipped, and we don't have that where I am. Our local is only tooled for programming keys on the Big 3.

Dealer is the only game in town here for Honda.

no there is no remote start,and i really dont know any other reasons.

Then my first reply will be correct.

The immobilizer and keys MUST be programmed before that car will run.

I see a tow truck in your future.






The owners manual explains how that green key light is supposed to act on page 81.

yeah unfortunately.

and you were right,called honda dealership and they said same thing,i have to take it in so they can program the key.

thanks for the help

Ask (nicely) if they can walk you through entering and using the "immobilizer brake code".
(The red BRAKE warning light MUST work when the handbrake is pulled.)

This would allow you to start the car and drive it to them, saving you a tow bill. The code would have to be re-entered every time you want to start the car so don't shut it off until you get it where you need to go.

thank you,i did that,asked them about it and they needed vin number,so they gave mi this brake code.
now once you start car with that code,and shut it off,you have 10 minutes to start it again,otherwise you will have to enter code again..

anyways,thank you all for help,problem solved.

key cyilinder online $250-$400,in stores $400+. junkyard $50 for whole steereng wheel component (airbag not included) and for programing it was $29 with tax,so total was $79 not bad

Holy cow, that's like dang near free. Was this at a Honda dealer? We are over double that for programming, and AFAIK we are half the price of the nearest 3 other dealers.

Yes sir,it was at Bobby Rahal honda dealership..

and on top of that,they did wiring for my headlights,since it has that callback.

Can't complain

Sounds like they did right by you.

Might go out of business due to "lack of profit".

They will get him next time when he comes in for something a little more serious

hey i hope they don't haha
but all i have to do with it is to swap transmission,paint it and it will be like a new.for that im not going to honda dealership

Dang, that is cheap for programming. Most dealers I know charge over $100, we charge $60