Does that Haynes manual have an ECU pinout or a wiring diagram of your a/c system?

 

Barely, it says that there are 2 red wires connecting to the relay (From PCM, to clutch).

I test some of the wires and see if something's not making a solid connection and try to trace the relay back to the PCM harness later this week.

Thanks for your suggestions.

 

Ok. I looked on the autozone website for the 98-02 3.0L accords.

The PCM pinout on there shows that A17 is a red wire going to the a/c controls (I am assuming the compressor relay) and the A27 is a blu/red wire (ac diode). I'll see what other information I can dig up.

 

Hmm, testing something. Ignore that post!

 

That description is difficult to follow. Can you tell me the other two wire colors going to the relay (I already know there is a thick and thin red wire)?

Do you have a volt meter?

 

Now I'm even more confused as to what is going on. I traced the wire from the PCM to the relay box, then ran a new wire. I traced the wire from the relay box to the compressor, and ran a new wire. I'm getting 12 volts between the two contacts at the relay box for the compressor, but I'm not reading anything between the PCM contacts (so I'm guessing it's not gounding).

I'm back to where I was the other day (the compressor isn't running) but now I know I have the right wires and have continuity. Am I bypassing something else that I'm not seeing by running the new wires?

 

Can you tell me the wire colors? And do you know how to use the continuity setting on your volt meter?

 

I didn't check what the other two +12 wires are, I'll take a look when I take it apart again, I just finished putting it all back together for the commute to work. Attached is a picture of what I measured at the relay. I re-ran both of the red wires. I am familiar with the continuty function (it's how I tested the wires from the relay to the PCM and compressor.

 

My mistake, the "used to read +12" note is wrong. That's hot when the ignition is on. So now it seems like I'm back at PCM not grounding.

 

Here is how I numbered your drawing:

1 2XXX3
XXXXX4

1 - 12V ? wire
2 - thick red wire going to compressor

3 - thin red wire going to pin a17 on ECU
4 - 12V blk/org? wire

With the relay removed, and testing on the fuse box with the key in the II position. Pin 3 to ground should be open. Pin 2 to the thick red wire at the compressor should be closed. Pins 1 and 4 should both have 12V.

Testing on the relay. Pin 3 to Pin 4 should be closed circuit. Pin 1 to Pin 2 should be an open circuit.

Let us know what you find.