Humming noise engine bay with power button off

[Henry W]

😀car has been unused for about ten days and is in the garage with Ctex charger connected direct to the 12 volt Battery.

Yesterday whilst in the garage I noticed a low humming noise coming from the engine bay.

I next went and got the remote opened the car pressed the power button hybrid Battery indicated fully charged seconds later engine started and all looked OK. Engine only ran for few minutes with the graphics showing a charge to the hybrid Battery.

 

 

 

.

[Paul Brooksbank]

It will be the inverter cooling system running. 

[Henry W]

Thanks for your reply 

Please advise why would the inverter cooling system be running and if this is normal with car power off and the car parked unused for several days

If this is normal then how long would it take to deplete the 12 volt Battery if it was not on the Ctex charger i.e. Is the inverter cooling system power load very low ?

I do appreciate any comments TU

 

 

[OldTrout]

Henry,

Is it the Ctex humming?

John

[olliesgrandad]

35 minutes ago, OldTrout said:

Henry,

Is it the Ctex humming?

John

That's a very good point. I haven't noticed mine humming but it is in the garage with a freezer nearby. 

[Henry W]

Thanks for the replies

The ctex is in the closed boot area adjacent to the 12 v Battery and the sound is definitely from the bonnet area

guess IF it's normal for the the inverter cooling system to run when the car is not in use this would perhaps be intermittent on temperature control 

regards

[Herbie]

40 minutes ago, Henry W said:

guess IF it's normal for the the inverter cooling system to run when the car is not in use this would perhaps be intermittent on temperature control 

That is definitely NOT normal. I can assure you that the inverter cooling system does not run with power off. Firstly, how could it and secondly, what would there be to cool?

The inverter only has things to do when the car is energised.

[Zotto]

Probably, the noise you heard is the NORMAL "purring" that occurs when you go with remote keys near the car, coming from brake electric pump to have the adequate pressure before starting engine.

[NemesisUK]

I thought that only started once the driver's door is opened?

[Zotto]

No, it starts when you approach to car.

[Illogan]

1 hour ago, Zotto said:

Probably, the noise you heard is the NORMAL "purring" that occurs when you go with remote keys near the car, coming from brake electric pump to have the adequate pressure before starting engine.

I wonder if our cat was a Lexus?

Although she's passed away now, whenever I went near her with a bowl of food she used to start purring too, and if I took the bowl away she'd stop straight away!

 

[NemesisUK]

54 minutes ago, Zotto said:

No, it starts when you approach to car.

Mmm.. Just tried this on my car and nothing happened until I opened the door.

Lexus-tech.eu for my car only mentions while the auxiliary Battery is connected, even if the power switch is off, the brake control system activates if the brake pedal is depressed or the door courtesy switches operated. Therefore when servicing the brakes do not open/close the doors or depress the brake pedal if the auxiliary Battery is connected. 

I would imagine there would be an additional warning about approaching the vehicle carrying the key fob, if what you say happened?

[Zotto]

It happens only when brakes pressure is low, not always.

[Herbie]

8 hours ago, Zotto said:

No, it starts when you approach to car.

I have a 63-plate RX450h Advance and if I unlock the car with either keyless entry or by manually pressing the zapper buttons, there's complete silence until I open the door and then you can hear the brake control system activating - but not on the approach to the car, only when the door courtesy switch is operated by opening.

[Zotto]

 May be so, my point was about not worrying for unknown noises coming from hybrids.

[Henry W]

THANKYOU all for your commnts

regards

[Henry W]

Update😀 Mystery solved

Noise is coming from my Horman overhead garage door motors when one of the doors is open !

 

[Spacewagon52]

6 minutes ago, Henry W said:

Update😀 Mystery solved

Noise is coming from my Horman overhead garage door motors when one of the doors is open !

 

Has it taken you since April to discover this Henry?

Brilliant result!

 

As Zotto says, you do get various "noises" with hybrids that you think are not normal.

 

My 400h HANDBOOK mentions these noises and says they are normal so don't worry!

I had something similar with an anti-static strap I fitted to a car. I have posted it on here somewhere.

It is a great feeling when you discover something like that! 

 

[Henry W]

Sorry for late update but only recently identified source

We are lucky to have smaller second car to use which has resulted in very low mileage in the RX this year due Covid restrictions ie cancelled holidays etc

stay safe

regards

[Illogan]

And I was hoping it would be emanating from the mysterious underground bunker built at the end of your road, - -  the one that has a regular stream of black Hummers (with totally tinted windows) going in and out of it every dusk, and those squiggly laser beams from somewhere behind it.

Oh - - you haven't noticed that!

Damn! - hope i haven't worried you........