Relay buzzing, HVAC blower and A/C live without key on

Good afternoon,

Go under the dash and disconnect the blower resistor and see if the issue stops.

The resistor may be shorted to power sending power all the time to the blower and the control head.

I attached the wiring diagram of the system. There is also a relay for the blower. Remove it as well.

https://www.2carpros.com/articles/how-to-check-wiring

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

https://www.2carpros.com/articles/how-to-use-a-voltmeter

Roy

Hey Roy,

Thanks for the input. I didn't get a chance to to check the blower resistor just yet, after work I inspected the drivers side underdash area looking for water intrusion and while I was at it I yanked the fuse panel and the GEM. Took them my lab to bench test and they both appear to be working fine. No sign of water inside either box. Cleaned the contacts and reinstalled.

Update:
After reinstalling the interior fuse panel and GEM assembly, the problem is still there. With the Key off and the HVAC switch to off, nothing happens. Switching the HVAC switch to on will make a relay click out in the engine compartment (RH side). So playing with it a little more, if I rotate the HVAC selector to the right (one click "Bi-level") the relay clicks and the fan will blow at whatever speed it is set on. I can turn the fan speed up or down as normal. When turning the mode switch back to "off" the passenger airbag disable light comes on for a few seconds and then goes out. Back on again with the mode switch, several relays begin to hum. One under the radio, The interior lamp relay, under the hood, the two relays next to the junction box, (i think these are for the towing package?) My Alldata is not working so I cannot look up any schematics and such.

This morning, the behavior is still the same but this time, no buzzing, but now the ABS light is on! Anyway there is more going on here than a bad relay.

Roy, could you grab me the schematic for what feeds Fuse 22? This should only be hot when the key is on, and it is hot when the key is off. Can you help me trace this back? I have a feeling my issue might be in the CJB in the engine compartment.

Okay, 22 feeds a lot of fuses. I attached the diagram for you to view.

If there is no power, the bus bar in the fuse block may be the issue. It would require removing it and either repairing it or replacing it.

Roy

Thanks Roy,

Actually I have the opposite problem. I have power to things that should have power only in "run" and "start" With the key "off", they should be dead. Instead I am getting power. I finally got back into Ford PTS and looked over the schematics. It appears to me that a probable cause could be the ignition switch. I don't have time tonight but I'm going to pin that out tomorrow and see if it has a short in one or more of the outputs for "run". Particularly pins A4 and B4.

I attached the procedure for the switch below.

https://www.2carpros.com/articles/how-to-check-wiring

https://www.2carpros.com/articles/how-to-use-a-voltmeter

I also attached the diagram for the switch as well for you to check.

Let me know the results.

Roy

Hello, I'm Danny.

I agree with Roy did you check the blower motor resistor? If the resistor is burnt, melted, etc it can do funny things. Hope this helps.