Rep Power: 117

Trying to sort out what's going on with the AC on our 2008 EX.
The AC won't disengage.
I've searched and read quite a bit..
One trouble shooting suggestion was to pull the AC relay and see if the clutch stayed engaged.
I pulled it and the clutch disengaged. Swapped in another relay and it engaged but like before would not disengage.

I don't want there to be any damage by letting it run continuously.
But I also don't want to pull the relay if it'll be a problem.
So,,,, Can I pull the AC relay and run the car without it?

 
Rep Power: 0

if the AC pressure doesn't go beyond a certain level, the AC don't need to disengage. There's probably nothing wrong with your AC, what's the issue exactly with your AC ? you can't run the ac without the relay in place

 
Rep Power: 117

The AC is turned off.
It hasn't stopped running for two days.
The compressor won't disengage.

 
Rep Power: 0

That sounds like a short circuit problem in the ac switch dial, pull the switch out and unplug it and see if the clutch disengage

 
Rep Power: 222

Compressor needs to disengage

 
Rep Power: 117

That's the problem, the compressor won't disengage.

It won't disengage when the AC is turned off.

However:
If I pull the relay it disengages.
If I disconnect power to the A/C Pressure Sensor it disengages

What's next?
Do I need to replace climate control unit?

 
Rep Power: 222

Is the relay stuck?

 
Rep Power: 117

I put in a new relay.
It still stays engaged.

Would running the self diagnostic test tell me anything?

 
Rep Power: 222

Maybe, never had to do one. Might be a bad control panel

 
Rep Power: 224

Looks like the ECM/PCM turns on/off the compressor relay. It would get a request message over a communication line from the HVAC controls.

 
Rep Power: 117

Looks like swapping in a new control unit is the next step.

Fwiw there were no trouble codes so hopefully this means the ECM/PCM are in good shape.
That is if they throw any codes.

 
Rep Power: 117

Getting some "conflicting? info on the part number for the heater control (buying used).

Part # 79500-SNA-A03ZA is the part number found Majestic Honda for our 2008 EX sedan (interchanges with 79500-SNA-A02ZA, and 79500-SNA-A01ZA).

But I'm seeing part # 79500-SNA-A020M1 as supposedly fitting too but I can't that part number at Majestic.
Some research indicates it might be for a Civic hybrid but not sure if that's correct.

 
Rep Power: 224

I cannot find 79500-SNA-A020M1 at all. 79500-SNA-A03ZA (gray color) or 79500-SNA-A03ZB (ivory color) is the correct part. At least for the 4 door.

You can probably get one for cheap from a junkyard instead of buying new.

 
Rep Power: 117

I couldn't find any Honda parts website like Majestic that listed a 79500-SNA-A020M1 as well.
But I've seen a couple like this one on ebay https://www.ebay.com/itm/296605339704 (check the pics) and not sure what to make of it. Will it work or not?...strange

I plan on going the used route and have been searching car-part.com.
Found a couple somewhat nearby. Just need to confirm they have the right part number. Even so that A020M1 still baffles me.

 
Rep Power: 117

I pulled the AC/ Temperature Control Unit to see what part number was on it.
Guess what I found: 79500-SNA-A020M1 (there's also "NH608L" after the M1).

This is kind of strange but it matches the part number on more than a few Units I've seen on ebay

But like you I can't find 79500-SNA-A020M1 anywhere as well.