Buzzing/Clicking Under Hood In Fuse Box

MMitsock · #1 (**permalink**) 09-08-2003, 07:47 AM

I'm not sure if this is normal or not. I noticed yesterday when I placed the key in the ignition of our new '03 Highlander 4WD, V-6 while it was in the garage with the windows down, without turning the key, I heard a click under the hood then a buzzing from somewhere under the hood. I opened the hood and the fuse box and it seams to be the relay marked A/F that is clicking. Looking in the manual I think this is something called the Air Fuel sensor heater relay that is activating. I couldn't tell where the buzzing was coming from. It sounds like a faint version of the old buzzers that reminded you when you left the key in the ignition and opened the door. I had the door closed when I heard the buzzing for the first time.

It is something we haven't noticed before but it may be we have had the windows closed or not had the key in the ignition that long before turning the key and starting the engine to hear the noise. It seams odd that just putting the key in the ignition without turning it would cause some type of heater to activate.

Does anyone else hear this on their Highlander?

MMitsock · #2 (**permalink**) 09-09-2003, 11:15 AM

Bump

Buzzard · #3 (**permalink**) 09-09-2003, 11:38 AM

Have you talked to the dealer about it yet? Dont sound normal to me--Buzz

MMitsock · #4 (**permalink**) 09-09-2003, 11:43 AM

I sent them an Email this morning.

MMitsock · #5 (**permalink**) 09-10-2003, 12:27 PM

FYI, I called two local dealers this morning and both said the relay click and buzzing are normal. Although they differed a little on explaining just what was happening they both said all Highlanders (maybe only '03's?) do this. One service guy said they had gotten so many similar questions about the buzzing they actually went out and put keys in the ignitions of all the Highlanders they had on the lot and they all did it. They called Toyota and were told the it is normal.

I know this sounds like the stock dealer answer "they all do it" but I would assume that if something was wrong the dealer would like to get some warranty money from Toyota to investigate and wouldn't have told us it is ok and normal.

mikeb · #6 (**permalink**) 08-16-2004, 03:35 PM

My 2001 V6 4WD does the same thing.

mikeb · #7 (**permalink**) 08-22-2004, 08:48 PM

It cuts off after a few minutes anyways.

stortoro · #8 (**permalink**) 02-20-2007, 11:13 PM

I was so bothered by that buzzing and clicking sound that I also just heard today. I have an '02 highlander that I bought brand new in '02 and today I placed the key in the ignition without turning and heard the same sound when I insert the key and disappears when I remove it. I also left it there and it eventually disappears after 1 minute or less. Without fully inserting the key I just put the tip on the key hole and I could hear a clicking sound. Hope this is truly normal. It's been 5 years and today was the first time I noticed it.

prae · #9 (**permalink**) 02-21-2007, 02:04 AM

Quote:

Originally Posted by stortoro

I was so bothered by that buzzing and clicking sound that I also just heard today. I have an '02 highlander that I bought brand new in '02 and today I placed the key in the ignition without turning and heard the same sound when I insert the key and disappears when I remove it. I also left it there and it eventually disappears after 1 minute or less. Without fully inserting the key I just put the tip on the key hole and I could hear a clicking sound. Hope this is truly normal. It's been 5 years and today was the first time I noticed it.

I've always figured it was the water pump or something along those lines??? My '01 1MZ-FE 4wd does the same thing.