Buzzing noise near to alternator/steering pump res

[Semnoz]

I'm trying to locate the source of a loud buzzing noise that I can hear when the car is at idle, and also when the ignition 'switch' is at position II (long press of 'On' switch without pressing clutch).

I can hear it cleary if I poke my head inside the RHS wheel arch, but haven't yet been able to remove the plastic wheel arch guard to access the steering pump/alternator region. I can also hear it if I poke my head down between the main radiator and alternator (or as close as I can get). It's not the swirl throttle motor (I've moved that and it sounds different), thermostat or anything else with an electrical plug going into it that I can access from looking into the engine bay.

It sounds like an electric motor that's stuck. If I open the boot, the pitch of the whining changes, which may confirm it's an electrical noise.

I left the car in ignition switch position II for about 20 minutes and the sounds never goes away, so it's not a stepping motor calibrating itself - or perhaps it is, but one that's stuck.

[Scooser]

I have the same noise on my 58 plate V70 D5 after I switch the engine off. It seems to go on for a minute or so, and is a cross between a buzz/whistle.

Someone will be along shortly to explain I’m sue, but I never taken it as sinister as the noise always happens

[Semnoz]

Originally Posted by Scooser

I have the same noise on my 58 plate V70 D5 after I switch the engine off. It seems to go on for a minute or so, and is a cross between a buzz/whistle.

Someone will be along shortly to explain I’m sue, but I never taken it as sinister as the noise always happens

Mine does that too, but this is a different noise; louder, more of buzzing than a whining motor/solenoid and from a different location. And it doesn't continue after I stop the engine (but does happen when I put the ignition switch in position II).

[cheshired5]

Does your alarm sound and function as expected?

[Semnoz]

Originally Posted by cheshired5

Does your alarm sound and function as expected?

Yes, just tested it and all is normal.

[Stephen2015]

Just a thought, what about the swirl flaps motor mine does this after turning the ignition off for a few secs.

[Stephen2015]

opps sorry, see your engine was running silly me.

[pierremcalpine]

Sounds like your brake vacuum pump may be acting up. On my P3 v70 the pump is located just forward of the battery and very close to the power steering pump. They are prone to leaking and require a service kit to replace the o rings. I suppose that if left to leak long enough it might cause pump to make “un-natural” noises....

[Semnoz]

Originally Posted by pierremcalpine

Sounds like your brake vacuum pump may be acting up. On my P3 v70 the pump is located just forward of the battery and very close to the power steering pump. They are prone to leaking and require a service kit to replace the o rings. I suppose that if left to leak long enough it might cause pump to make “un-natural” noises....

The electrical buzzing noise doesn't change when I move the steering wheel. And it happens when the engine isn't running.

[Ed Mac]

I have exactly the same thing going on with mine. Did you ever identify where the noise was coming from?