If there's a better forum to post this in please let me know!

2000 CRV 4WD 4AT

Long story short:
Just the other day I fixed an intermittent no-spark condition on my CRV by verifying no signal coming from the ICM to the Ignition Coil. Replaced ICM, good to go.
Since the issue was intermittent, I had set up a test board so I could watch various signals at once since the issue was intermittent and would go away on its own while trying to take everything apart to test.

I think I managed to short out two of the test leads: ICM trigger signal from ECU and ICM output signal to Ignition Coil while the engine was running.
It died, and now will not start. As of now, I am not getting any signal pulse to the ICM from the ECU.
I have verified continuity from the ECU output to the connection at the ICM. I'm also not getting a CEL.

Today I am going to carefully back probe the ECU and verify I am still getting signal from the CKP and CKF to the ECU. Not sure why I wouldn't be, but if I'm correct the ECU needs that to trigger the ICM.
**Question: Are both of these signals required to run? As far as I understand, the ignition runs off of CKP feedback, and CKF feedback is used for trouble codes related to misfiring etc. Please correct me if I am wrong.**
I am also going to put the old ICM back in and see if anything changes (it would work until engine warmed up). Would be awesome if I just fried the new ICM and need to replace it again, but not getting my hopes up.
Will also plug in my code scanner and see if anything pops up.

I am considering swapping in a used "verified good" ECU, but I would like to eliminate any other possibilities before doing so. Thought about seeing if there was one to pull at a local yard (risky?), or order one from Ebay.
**From what I've seen/read, these ECUs are plug and play, can someone confirm?** (Part # 37820-PHK-A53)

Are there any other troubleshooting routes to take before calling the ECU bad? I have taken it out and inspected the board, nothing is obviously wrong with it, or the connectors at the ECU.
I am still doing my research on this. I am seeing a lot of info about diagnosing ignition issues from the ICM then on downstream, but not much regarding lack of signal to the ICM.
Any advice would be greatly appreciated! I'll be back with any findings from later today.

Thanks,
Boom

 

Quick Update
I was unable to find anything wrong except for the fact I am not getting the ICM trigger signal from the ECU.

Both power sources from ECU (Connector B, pins #1 and #9) show voltage.
Getting AC voltage from both CKP and CKF to the ECU (Connector C, pins #8 and #22)
Nothing changes when I install my old ICM. Even though it was faulty, I was always seeing the trigger signal to it from the ECU regardless of if it was working or not.
Code reader was able to connect. No codes, I did see that RPM signal was working while cranking/watching live data.

Still trying to read up on this, but at this point I have exhausted what I know to try.

Looking into getting a used ECU from Ebay or something if I can't come up with anything else to test.
It looks like they are $60-$70ish online, would cost ~$90 the local yard to pull one and get their "warranty"
Is there any compatibility between different model years at all? I know it needs to be same engine, trans etc.

 

Have you checked to see if you have a fuse for the ICM circuit ? Many Honda applications do... just make sure you simply don't have a blown fuse.

 

I've checked all fuses in the fuse panel under the driver side dash and the fuse panel under the hood, passenger side. From what I can tell, the ECU output to the ICM isn't fused, or at least there was continuity between ECU and ICM when I checked last, but I will verify.
(The only ICM-related fuse I know of is the fuse for the ECU/ECM whatever you want to call it)

While monitoring signal from ECU to ICM, I detect path to ground with key in AUX, then no ground with key in ON. (behaves like it did while everything was working properly) Then when I crank, I get nothing.

Thanks for the input.

I feel like if I try a new ECU and it doesn't work, I will be stumped, so that's my last resort at this point.
There's a yard 30 minutes from me with 2 2000 CRVs. Costs more than getting one online, but with their warranty I could take it back no hassle if it didn't work and I'll be out $15. (If they have ECU still intact)

Is there any ECU compatibility between years or does it have to be exact match? Still researching this. Looks like I could potentially use a 2000 or 2001? (37820-PHK-A53)

 

Grabbed a 37820-PHK-A53 from a 2000 CRV at the junk yard ($100 all said and done w their warranty). Plugged it in and it fired right up.