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I have a 04 Civic ex K20 my key was stolen only had one key computer won't read at all to get a key programmed anyone kno what I could do?
any help would be greatly appreciated Thanks!
Can't talk to the ECU because the ignition is off I imagine.
You may need to get another ignition switch with matching keys, then have a locksmith program. Unless you want to figure out how to get ignition on with no key. Even then I'm not sure the locksmith can make a new key without having one to copy.
Should I buy a new ECM? The computer won't read at all I hook up a obd 2 up an it won't even turn on I took it to a shop dude hooked up his computer nothing happened and thanks to everyone helping I'm just a young kid with no help so it's greatly appreciated
Can't talk to the ECU because the ignition is off I imagine.
Again, if you don't have a key to turn the ignition on you will never be able to talk to the ECU. Buying a replacement ECU is a waste. As far as I can tell you have four options:
1. Basically hot wire the car to get ignition on without a key. It won't start like this but will allow a locksmith to talk to the ECU. Not sure they can make a new key without an original to copy though.
2. Buy a replacement ignition switch with matching keys. Then take it to a locksmith/Honda to get programmed.
3. Buy a replacement ECU with matching ignition/keys. No programming would need done but you're talking about hundreds of dollars here.
4. Take the thing to a Honda dealer and let them fix it. I believe they can lookup and cut a new key for your ignition. They can then program it into the ECU as well.
All of these will be more difficult since you're K swapped and the ECU does not match the car. Usually programming requires the ECUs VIN. You could try the VIN on the engine but who knows if they're from the same car. Do you know what engine you have in the car? K20a, K20a2, K20a3? Any idea if the ECU came from the same car as the engine?
Last edited by BrotatoChip; Oct 8, 2020 at 04:03 PM.
You don't need engine run to talk to ECU
II is enough.
If the physical key is not working you can remove the cylinder and turn the ignition switch directly.
I have a key it turns the power on to the car but has the security key light on an I can't get the computer to read to be able to program a key I ran the VIN on the block an it said no results??I know it's a k20 tho
I didn't really get that much information about the car when I bought it...it just looked really nice an was fast 🤣 so ya kno being a young kid in a city with rice rockets everywhere I had to have it so I have no clue if the computer came out of the rsx that's where the motor came from
I have a key it turns the power on to the car but has the security key light on an I can't get the computer to read to be able to program a key
I guess I misunderstood your first post. You said key was stolen and only had one key, thought that meant you now had no keys.
Anyways, if key is on and you can't talk to the ECU I would start checking fuses. If the ECM is missing an ignition/power it would cause the security light to flash as well. Taking some guesses at fuses here: under-hood fuses 6 and 7, under-dash fuse 17.
or check the ecu - it's behind the glovebox.
wasn't most of the engine swaps using a modified ECU, like hondata?
Not sure how the immobilizer worked on ECU modifications.
All fuses are good everything is plugged in to the ECU BUTTT I have two wires a black an white one an a red an yellow have no clue what they are for or where they go anyone got a idea?
All fuses are good everything is plugged in to the ECU BUTTT I have two wires a black an white one an a red an yellow have no clue what they are for or where they go anyone got a idea?
We are going to be in the same boat. You'll have to trace the wires back and find where they originate.
