Random Click - 71 Blazer

[ochre1971]

Just like it the title says, I'm hearing what sounds like a random (seemingly) relay click sound. I happened to notice it the other night while getting a picture of something under the hood for a fellow member. I was in the area of the battery and thought I touched or moved something. Couldn't reproduce it.
Now, at least twice since then I've walked through the garage and heard this same click. One other time as I opened the driver's door to get something...

It sounds like it's coming from behind the AC compressor area, possibly inside the cab in the same area.

All this is obviously while the truck is off.

Anyone have any thoughts as to what this may be? Thanks in advance.

I posted this in the electrical section as well, but thought I may get lucky and find someone over here who has dealt with this before.

BP

[hemi43]

Mice.

[GMC-YA68]

turn that fan flower on! I had an old dually that the fan blade had spun out on, opened it up and figured out why...

[rsavage]

I believe there is an AC relay under the passenger side dash towards the glove box (mounted to the bottom lip of the dash. You could check that out. Are you having any parasitic draw on your battery?

[simicrintz]

Originally Posted by GMC-YA68

turn that fan flower on! I had an old dually that the fan blade had spun out on, opened it up and figured out why...

That stuff is legal in several states now

[Okie528]

I had something similar on mine right after we replaced all the wiring harnesses with AA harnesses. It would happen with the key off just randomly. A little unnerving as a dead short and close call electrical fire prompted the rewire. The guy I had do the electrical work looked into it, and said it was an anti-dieseling relay, (maybe in the a/c harness?)apparently he just disconnected it, no more clicking.

[ochre1971]

Thanks guys for the input. I'll play around with those relays. I have noticed that occasionally I get a few sputters after shutting down, the AD relay may have an issue.