Electric hum sound when car is in 'ON' position.

[adgjqetuo]

Is this normal for when the car is at the 'ON' position without the engine running? I've never had a car this loud in this mode before.

 

[paris1]

Didn't hear a thing.

 

[tibimakai]

Probably the fuel pump. On my ex VW, when I opened the driver's door, the pump would turn on(!).

 

[MikeM.]

That's loud?

 

[Bopper]

I do believe that mine makes a hum even in the off position after shutdown. I walk past the front of my car when I get home and I can hear a hum, I have never stood there and timed how long it continues.

 

[adgjqetuo]

It's def way louder in person. I noticed it while I was adjusting some of the personalization settings this afternoon. As soon as I push the car off it goes away. It's when you press the button twice without the brake so the car is on but the engine isn't.

I don't think it's the fuel pump that should just be a prime noise that goes away after a few seconds. This never goes away as long as the car is at the 'ON' position. It's coming from the engine compartment.

I will try to take another video today - maybe with the hood up so it plays more distinct in the video.

Previous cars I've had have been / are completely silent while at the on position which is why I found it odd.

 

[adgjqetuo]

Here is another video - it's a little longer but hear it out.

There isn't any noise when engine is off or on ACC mode, but when it's set to ON mode it's there. I went through all 3 modes and got a little closer so the mic picks it up better.

 

[tibimakai]

The fan is on or off at the climate control?

 

[adgjqetuo]

Nope, it was too cold in the garage and the blower wasn't running.

 

[SayNoToPistons]

Given the amount of electronics, modern cars have plenty electrical noises.

I cannot pinpoint exactly want that hum is, but it is normal. It's more of a whine. Hear it on my 2013 2.0 and my girlfriend's 2015 2.5. The noise is similar to what I hear in the E90 and F30 3 series along with many other cars.

 

[paris1]

I just checked my 2013 and heard the whine you're describing as soon as I hit the start button. It continued through the second button push and continued still after I hit the button a third time and the ignition was completely off. It stopped a minute or so later of its own accord. My guess is that it's the electric fuel pump that shuts itself off once the system is pressurized. I also find this kind of thing not in the least bit alarming given the complexity of modern automotive electronics.

 

[adgjqetuo]

Thank you for the confirmation! My '13 Subaru is virtually quiet when set to 'ON' so it was different to me. This is my first Mazda so I thought I'd ask. I do agree with computers / electronics. It sure does have a lot of systems on board.

 

[magicpotatoes]

could it be the fan that cools down the infotainment/head unit?

 

[minnesotaart]

I have always attributed mine to the headlights on my 2014 GT w/tech. I park in the garage and the headlights always go on before I shut the engine off. Maybe try setting the headlights to off (vs auto) and see if that makes a difference when you park it in the garage.

 

[jev]

Nah, what you're hearing are these guys, warming up:

(okay, these guys are from the old MX-3 V6 but hey, I guess they're in the CX-5 too!)

 

[paris1]

Nah, what you're hearing are these guys, warming up:
(okay, these guys are from the old MX-3 V6 but hey, I guess they're in the CX-5 too!)

Fun factoid: at the time of its production, the 1.8 ltr MX-3 engine was the smallest production V-6 on the planet! That record may still stand.

 

[madar]

may be an EVAP pump. Some manufacturers use a vacuum pump in the EVAP system to check for leaks.

 

[GP 2004]

My cx-5 makes a noise like what you are describing. I mentally wrote it off to something electrical, and forgot about it. I figured if it fails I'm covered by a warranty.