You are correct that you have 3 relays. However, the PCM only actually grounds two of the relays because the Fan Control relay and the AC condenser relay control sides are tied together on the same circuit from the PCM. The third wire coming from the PCM (First wiring diagram with the black arrows) is to ground the PGM relay.
To address what you are seeing with not having voltage on pin 4 of the AC fan relay we need to look at the second wiring diagram.
The power starts at where I added number 1. We need to check fuse 11 to make sure you have power there. Then follow power down to number 2. The PCM grounds this relay on terminal 3 of the PGM relay. When this is grounded, the relay closes and power goes from terminal 1 of the relay to terminal number 2 of the relay (where I added number 3). It then goes to fuse 15 and then through the diode finally to number 4 that I added (also terminal 4 of the AC relay) which is where you are not getting power.
So you need to go backwards through this circuit to find where you have power and where you do not.
Let me know if you have questions. Thanks
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Wednesday, July 1st, 2020 AT 7:37 PM