Another relay box? What is it?

[sceva]

I discovered a second relay box under the hood of my 97 explorer 4.0 sohc. Its on the passenger side under the air intake hose (next to the box). One of the relays is buzzing and I am wondering what those relays are for? They arent in my Haynes manual or the owners manual. Neither book even acknowledges the box exists. My 4 wheel drive also quit working recently... Do any of these control the 4x4 system? Thanks in advance!

 

[2000StreetRod]

Aux Relay Box

On my 2000 it's called the Auxiliary Relay Box. There's a drawing for a 1999 in the following thread:
1999 Mountaineer auxiliary fuse box diagram.
There were some significant wiring changes in 1998 so I don't know how similar a 1999 is to your 1997.

 

[Electrohacker]

all I know is I snatched one up when I was at the junkyard because it had 2 40 amp and 2 20amp relays and an open hole for a third relay if I can add the contacts

 

[kladaniels]

1999 Ford Explorer Auxilliary relay box

This info was fantastic. I went to the dealer today and they could not help me get the diagram. I was able to fix my washer pump problem for nothing since I got some relays from the wrecking yard.

 

[sceva]

Ok, I figured out what is going on but not what is causing it. I replaced the buzzing relay and it didnt stop. However I noticed it only buzzes when the heat in the front is on... I have the rear climate control too... The rear climate control doesnt work when the main heat is on... but when I turn the main heat off, the relay begins buzzing and the rear climate control turns on...