Hello Everyone. New to the site in hopes to find some help with this project.

I previously purchased an 04 Civic DX shell. Went out and bought an EX harness, EX ecu, and an EX engine. Got everything installed and now car will not crank. New starter and battery so not sure what the issue is.

Was told it could be immobilizer. Anyone have any ideas?

Thanks for the help.

 

Were the car keys programmed to the EX ECM/PCM? It needs to be programmed due to the Immobilizer system.

 

No they where not. How would I go about getting the key to match the PCM? Thank you so much for helping me with this.

 

Some locksmiths have the hardware/software to program the keys, Immobilizer receiver, and ECM/PCM for the Immobilizer system.

Other options would be dealer, or buying a immobilizer key programming tool and doing it yourself.

 

Thank you so much for the help with this. Contacted a local locksmith thay specializes in this. Lets see how it goes. Really appreciate the help

 

So just had the key reprogrammed and still no go. Still same issue but now when I the turn key i can here a click from the starter and then loss of all power completely. Could this be a relay issue? New battery and starter are installed. Thanks

 

1. Turn the ignition switch ON (II), and check the immobilizer indicator indication. - Don't try to start the car.Does the indicator come on for 2 seconds, then go off?
2. Is the green key symbol (immobilizer symbol) flashing on the dash when you are trying to crank it?

It may still be related to the immobilizer programming/registration. There are several items that can be registered/program, such as:

• re-write keys
• replace/registration of the immobilizer-keyless control unit (receiver located next to ignition switch)
• replace ECM/PCM
• replace MPCS/MICU/IMOES (if under-dash fuse box replaced)

See this other thread (post # 7) related to an earlier generation Civic, where the locksmith didn't program the required item: https://honda-tech.com/forums/honda-...-hell-3352733/

3. Also, can you use the remote transmitter to unlock the door without issue? If there are issues, it may be due to Ground G101.

 

I can't thank you enough for all the help. So car is now running! Looked like it was the immobilizer. Now running i have an issue with the idle bouncing from 1500 rpm to 800 rpm and has a clicking sound in the glove box. Could this be a bad relay?

 

The relays behind the glove box that are clicking are either one or both of the main relay 1 and main relay 2. Probably not an issue with the relay.

Check Ground G101 and make sure it is tightly secure.

 

Thank you for all the help. So after weeks of troubleshooting and a hefty locksmith bill, It turned out to be bad ground and faulty ecu.
remade all the grounds and bought a new ecu.
Now the issue with the immobilizer is back and locksmith is telling me they might not be able to program the key and immobilizer to the ecu but still have to pay $150.00 just to come out.
Would this be a dealer issue now or is there a way to bypass the immobilizer? Thanks again for the help

 

Common issue is the alternator bolts become loose and lose ground and fries the PCM.