Buzzing noise coming from my fuse box

MysticMac

Well-Known LVC Member
Joined
Aug 18, 2015
Messages
410
Reaction score
42
Location
Vancouver British Columbia
I've needed to jump my car every time I start it because my battery is hooped and over 5 years old. It goes dead after I turn the car off and unless I undo the negative terminal I get this weird buzzing noise coming from Relay 010 in the fuse box under the hood. Anyone know what this could be?

InkedGOPR3130_LI.jpg
 
It's turning on and off continuously.
Relay 010 - blower motor.

-Bad wiring/no good contact
-Bad relay
-Bad signal(could be your battery )

It will end your relay lifetime.
I don't know if the blower motor belongs to AC system but if not escencial you could disconnect until repair.

Do you have el AC on when starting the car?
 
Last edited:
makes noise with relay removed

Well that's discard the relay,
I don't know what else could be.

Switch position ? Off/On/accessories?

Are you sure it was the relay 010?

Do you feel any vibration?
 
Well that's discard the relay,
I don't know what else could be.

Switch position ? Off/On/accessories?

Are you sure it was the relay 010?

Do you feel any vibration?
010 vibrates then when i remove it it makes a slighter buzzing noise... whats the chances of it being a bad battery?
 
wiring should be fine the harness looks like its never been touched before and i keep the engine bay pretty clean.. i did have a leak but not enough to corrode the wires i dont think.. i have no heat issues at all so my blower motor is good i think.. i think im going to swap relays and change the battery
 
You can connect a multimeter and read if you get good signal.

Yo can swap the relay.

Of course,should get a good battery.

Just some info about relays may point out to the issue.

The relay have a rated voltage to close the contacts providing 12v at coils. It has tolerances, you could turn on the relay with 9v there are other voltage,"retaining voltage" the minimum voltage to hold the relay on, it could be -%30, well if you battery fluctuate with the loads when the relays turn off for lack of voltage the battery voltage rise again and the relay turns on and off because enters at resonance state.

Relay turn on voltage
Relay retaining on voltage

This is not common ,
Relay near end lifetime
Bad power supply
Bad signal also means bad contacts, corroded ones.

The buzzing it's something switching on and off.
Sounds like a relay,slow switch not more than few kHertz.
 
You can connect a multimeter and read if you get good signal.

Yo can swap the relay.

Of course,should get a good battery.

Just some info about relays may point out to the issue.

The relay have a rated voltage to close the contacts providing 12v at coils. It has tolerances, you could turn on the relay with 9v there are other voltage,"retaining voltage" the minimum voltage to hold the relay on, it could be -%30, well if you battery fluctuate with the loads when the relays turn off for lack of voltage the battery voltage rise again and the relay turns on and off because enters at resonance state.

Relay turn on voltage
Relay retaining on voltage

This is not common ,
Relay near end lifetime
Bad power supply
Bad signal also means bad contacts, corroded ones.

The buzzing it's something switching on and off.
Sounds like a relay,slow switch not more than few kHertz.
thanks ill throw the multi meter on in the am when i have light... ill keep in touch !
 
I'd pull every relay and see if the noise persist.

for locating noises like this, a $4 stethoscope is a worthy investment...
Mechanic's Stethoscope

I pulled everything out one by one until the noise went away and it ended up being relay -03 which controls my fog lights.
When I put on my new bumper I disconnected my fogs lights but I'm not sure why that would make the relay start buzzing?
 
When I put on my new bumper I disconnected my fogs lights but I'm not sure why that would make the relay start buzzing?

it wouldn't... the fog lights are on the output side of the relay, there is no connection to the trigger side of the relay. either the computer is sending out a weird low voltage signal (just enough to hover around the threshold that triggers the relay) or you have a problem with your wiring. example: if that relay has constant power and needs a negative trigger(I'm not sure if ti is or not), and there is a partially shorted wire, or a bad/corroded connection or junction, it could be allowing just enough current to pass to keep activating and deactivating the relay.

does the noise stop when the fog lights are switched on?

use a meter to measure the voltage across the relay's coil terminals. I'd also measure resistance to ground on the coils negative terminal when resting and when turned on.

there have been a few issues with the LS where something happens to that bundle of wires near the fuse box, I wouldn't be surprised if that was the case.
 
does the noise stop when the fog lights are switched on? - the noise stopped all together once I pulled the relay and put it back in. I started the car back up (with my booster pack) and ran it under 5 minutes and turned it off and the noise went away completely now. I returned my motorcraft battery about a month ago because I was going to get a battery from costco for a half the price because of a costco cash card I got from a price drop in a tv I purchased. It turned out the battery for a continental and returned it back to costco only to find out they dont have any LS batteries in stock anywhere in Vancouver BC Canada to Bellingham washington US and they will need to order one in and they cant even guarantee they have any of them. I am hoping my shitty battery is causing this. Either way im going to try and understand what you want me to do with my multi meter tomorrow and get my friend Hawk to help because hes way more electrically inclined than I am when it comes to cars.

I dont thnk i had my fogs on the last time i started when the noise went away. what would that mean? I just dnt see how my wires could get corroded. Its been parked for little over 2 months with no water or anything anywhere close to the fuse box under the hood but im not ruling it out. where should i start looking?
 
Your probably know this already Mystic, but make sure that's a Mega-Tron 66 Plus. When I talked to Costco they said they didn't carry that, so thought I would mention it. Don't want the gases in the car you know!
 
You are killing your alternator by running the car with a bad battery.

The fog light relay is a "negative trigger" from the FEM. It is a black wire with green stripe.
 
Your probably know this already Mystic, but make sure that's a Mega-Tron 66 Plus. When I talked to Costco they said they didn't carry that, so thought I would mention it. Don't want the gases in the car you know!
would you suggest getting a Motorcraft or any Mega-Tron 66 plus?
 
would you suggest getting a Motorcraft or any Mega-Tron 66 plus?
I've been using a NAPA Legend (vented group 65 IIRC) for the past few years without issues.
More CCA than stock and it was fairly inexpensive.
 
I have always used Interstate, but this time I went Motorcraft due to cheaper and easier to get. Either one will be fine, just important to be the 66. I pulled a brand new 65 (autozone ish) PO had bought to get it going, thankfully got 50 bucks off of craiglist for it.
 
Yes I bought the battery over the phone with the credit card today at noon. they didnt have any in stock but its being shipped from Edmonton BC and should be here tomorrow afternoon. Someone must have bought two of them because they had two in stock just last week lol.
 

Members online

Back
Top