Buzzing noise near under hood fuse box

2004 GMC SAVANA

250,000 MILES • 5.3L • V8 • 2WD • AUTOMATIC

PAULMREID

MEMBER
2 POSTS
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Something near my under hood fuse box just started making a buzzing sound all of a sudden the other night when it hadn’t even been running for several days. The only way to stop it was disconnecting the battery.
What should I start looking at?

May 28, 2020 at 1:57 PM

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JACOBANDNICKOLAS

AUTOMOTIVE REPAIR CONTRIBUTOR
110,190 POSTS

Hi,

That's a tough one. Is it possible for you to record it and upload the sound for me to hear? Also, what I would do is open the fuse/relay box and touch the relays to see if you feel it. If not, remove one fuse at a time to see which fuse stops the sound. At that point, we will have at least identified the circuit.

I attached a pic of the fuse box and the legends identifying what each fuse controls. Try that and let me know what you find.

Joe

Images (Click to enlarge)

May 28, 2020 at 8:08 PM

PAULMREID

MEMBER
2 POSTS

Thanks Joe,

I reconnected my battery yesterday but the noise or chattering was gone.
At the time this happened we had just had a lot of rain for days. Could high humidity cause a small short in a relay and then dry out and be okay again. If it happens again I will try to get the sound recorded for you.
I’ll be in contact if it continues.

Thanks again,
Paul Reid

May 31, 2020 at 9:35 AM

JACOBANDNICKOLAS

AUTOMOTIVE REPAIR CONTRIBUTOR
110,190 POSTS

Hi, Paul.

Honestly, anything is possible. Let's just hope it's gone for good. Regardless, if it does return, let me know.

Take care of yourself.

Joe

May 31, 2020 at 7:09 PM