Random electrical clicking

[RobsRanger]

OK so in my Ranger while driving I get this weird electronic click from somewhere in the cab. It kind of sounds like when your AC compressor kicks on, but it's not that. I do think it has something to do with the venting or heating system though because... If I have the vents set on the defroster I hear the click maybe once every 15-20 seconds. If I have it on the front face vents it's maybe once every 45 seconds. If it's on the feet, it doesn't click at all. It's pretty audible; I can hear it over the radio unless it's cranked. I don't know hardly anything about electronics or relays or servos or whatever. I can wire a sound system but that's it.

The only other thing that might be of interest... The truck used to be a government vehicle, so it was wired with all sorts of stuff. It had a PA system because the speaker is still in the engine bay. There's also some kind of weird black plastic sphere with wires coming out of it in the Engine bay that's about the size of softball (never seen anything like it before). You can see all the screw holes in the plastic under radio where they had switches and PA microphone mounted.

Anyway, any help would be appreciated, the clicking is pretty annoying.

 

[RonD]

Well the Vents in the cab are vacuum operated
Only thing electric is the Blend Door actuator and its controlled by the TEMP knob , these are a know issue in Fords, but they usually stop working so no heat or too much heat

You can pull fuse #27(10 amp) in the cab fuse box, that powers the Blend Door actuator but also Blower relay so no fan
Just to see if that may be causing the clicking

You can get your 2007 owners manual here: https://www.ranger-forums.com/general-technical-electrical-18/ford-ranger-owner-manuals-1996-2011-models-3747/

Then pull other fuses to see if any stop the clicking noise to maybe narrow down what it is

 

[RobsRanger]

Well the Vents in the cab are vacuum operated
Only thing electric is the Blend Door actuator and its controlled by the TEMP knob , these are a know issue in Fords, but they usually stop working so no heat or too much heat

You can pull fuse #27(10 amp) in the cab fuse box, that powers the Blend Door actuator but also Blower relay so no fan
Just to see if that may be causing the clicking

You can get your 2007 owners manual here: https://www.ranger-forums.com/general-technical-electrical-18/ford-ranger-owner-manuals-1996-2011-models-3747/

Then pull other fuses to see if any stop the clicking noise to maybe narrow down what it is

Hmmm. Well everything works normally, so it’s probably not that blend door actuator. Everything works fine, there’s just an annoying ticking. I’ll have to check the fuses and see if I see anything glaringly obvious.

 

[Mike Tonon]

Sometimes mine does this. If I turn the temperature knob an inch, then put it back where it was, it’s gone for a while.