e46m3c

Bit of a strange one here. I am after some ideas.

2006 z06. Previous owner changed the battery to a hsb013 which I assume is sufficient. The car stats fine.

If i rev the car stationary. When the rpm gets above 4K, and starts to fall, a buzzing sound happens from the dash. The volume of the buzzer changes. It's not binary on/off. It's quit intermittent. As far as I can tell it doesn't buzz when the revs are rising. Only when falling. Also I'm not sure it buzzes when the revs are max. Don't recall hearing it at trackday last month. But perhaps I just wasn't paying attention/ couldn't hear over 175mph road noise!

Previous owner Isn't sure if this was there before the battery swap as it had a stupidly loud exhaust on it.

Suspect the battery.

Noticed the positive terminal had cracked and so replaced the terminal on the cable.

Also replaced the negative terminal and the noise reduced a little. But could be false.

Ran the the car with a data logger and all the time I'm getting 14v. Even with the buzzer sounding.

Aux belt is not the most taught but if that was a problem I would expect to see it in the logger.

Right now im thinking my next move is to put a different battery.

Or or perhaps there is an earthing fault somewhere?

i am in the uk so not great vette knowledge about.

Hope you you guys can fire some ideas my way. Or perhaps someone has had this issue also?

Cheers
chris

e46m3c

One more thing to add which may not be relevant. Sometime the right side indicator blinks at double speed. Even though all bulbs are working. This could just be a dodgy connection on the rear as I had them off soon as I bought the car.

Sabre34

Welcome to the forum. Unfortunately I don't have an answer for you but I'm sure someone here will. You may also want to post your question in the Tech/Performance section.

e46m3c

Oops sorry. Can a mod/admin shift it?

Boomer111

Well the most common cause of the buzz from the dash are is the front window cowl.

It vibrates at speed and more so when it is warmer out.

It sounds like bees in a can!

You can do a search for cowl replacement of dash buzzing.

You might need a new cowl and the last time I checked it was a $90 part. It can be replace easily enough with the biggest issue is pulling the wiper arms off. If you have a puller it makes this easier, but it can be done without the puller just takes some finagling.

Basically there are 5 tabs that need to be secure to the bottom of the front windshield glass. Some caulk is applied to the tabs helping them adhere to the glass. If a tab is missing or broke the cowl vibrates causing the sound.

Simple test is next time you hear it buzz apply some tape along the edge of the cowl and the window glass, usually in the right corner is the spot.m If it stops then you have the answer.

Plenty of threads on this subject just do a search.

GM even put out a TSB I believe regarding this problem and a fix.

Boomer111

https://www.corvetteforum.com/forums...ion-12-gs.html

Above is one thread with the GM fix.

I used plan old caulk I had laying around.

here is another: https://www.corvetteforum.com/forums...ndow-seal.html

e46m3c

Thanks but it is definatley an electronic buzzer.

Does it stationary

Boomer111

Ok another common dash noise is the climate control sensor. It is the grill located just below the start button.

The sensor has a fan and it can detach from the clip. Reach under the dash with the power off and see if it is out of place, loose.

If it is it can buzz.

Boomer111

I had, in another car, a crack in the heat shield for the manifolds and it vibrated.

Good luck chasing it down, I am out of ideas.

e46m3c

How about this to test if it's the battery or ground issue

have the car connected to another car which is running. If the buzzing stops perhaps it's the alternator.

Diconnect the poaitive and leave the negative. If it's stopped it could be the battery.

Might be be cheaper than swapping the battery.

Ill give this this a go and get the multimeter directly onto the alternator just invade the diagnostics are not right.

Corvette_Ed

You need both the battery and the alternator to run the car. Trying to run off of another car that is already using its own power to run isn't going to produce enough voltage.

dryadsdad

Open the hood. Get someone else to rev the engine while you track to see if it's battery or alternator.

e46m3c

Tried jumping it to another car today and it made no difference.

I put put my head near the dash and it sounds like it's coming from the top left of the dials.

Doesnt sound like it's coming from the two grills to the right of the steering wheel but it's hard to tell.



Next next step is probably to take the dash apart a bit

any tips?

dryadsdad

tip:

learn to live with it.

Boomer111

On a side note one good thing with hearing loss is the Vette is less quiet.

e46m3c

Changed the terminals and gave it a good charge. Still buzzes. Oddly if I'm off throttle it buzzes. But if I apply some brakes it stops.

Next I'll try revving with the brakes. And take underneath the dash off

it does sound like it's coming from the binacle itself or top left ish/center of the dash

Kenny94945

Start with the outer W/S cowl panel mentioned above.

This "noise" has fooled many as they think the noise is in the interior.
Start by masking taping the cowl to the W/S on the outside.

Rattles can be frustrating.
AC sensor fan next to the start button is common for making a noise.

Could be anything that has loosened.
Sometimes taking a passenger to help press on interior panels while you drive helps in the hunt.
You never know maybe the noise is coming from the undercarriage in the rear?

Good luck.

e46m3c

Fixed it.

Put the windows down, and exhaust in loud mode and i cannot hear it anymore. It must have stopped

dryadsdad

Very smart fix. Should be a sticky.

e46m3c

Bit of a strange one. This ended up being a split grommet on the vacuum hose to the brake servo. How bizzare!