Buzzing Sound - Ignition
 

Hi, Normally when the ignition is switch turned on, there is a buzzing sound for a few seconds and thereafter the buzzing sound stops. My question is:

1. What does this buzzing sound indicate?
2. Lately the buzzing sound does not stop. What could be the reason for this?

Thanking you in advance to for the valuable information.

Hi,

What year, model, petrol, diesel, etc?

And is the buzzing from inside or outside? My wild guess is it's from outside and it's the fuel lift pump (Diesel, rear filter/lift pump version) that runs for a few seconds at initial ignition on and turns off automatically. If it's not stopping then this is unusual as it's not fuel pressure controlled, but controlled by the ECU.

Of course, that's a total guess!

Buzzing sound - ignition turn on
 

[QUOTE=andyb2000;105185]Hi,

It is a Chrsyler Voyager - 2004 - 2.5 CRD Diesel.Yes, the buzzing is from outside so I think your guess is correct. Thanks for the great advise.

I have been using the vehicle and it seems to be operating fine. Would I be doing any damage to the pump by continuing to use the vehicle. Do I have to replace the pump of replace any of the relays? If I need to replace the pump where can I get one? The dealer in South Africa does not have stock of pumps for this model / year.

Hi there, no problem it certainly sounded like it!
Now, it running all the time is a little worrying, it should only run for a few seconds at ignition on. So just check that first.
Turn ignition on to 2nd position (don't start car). Listen for noise, wait up to 2 minutes. Is it still running? If so then something odd indeed.

You probably aren't doing it any harm running all the time, however the pump won't be designed to run constantly so will wear out faster. The pump itself isn't at fault here, it's the control/power to it that's at fault.

I wonder if the lift pump relay is stuck? Check in the fusebox, to the bottom left you'll see "Lift Pump relay", so pull that relay out and it'll stop the relay working, swap a different relay to test (Horn relay is usually a good one to use) and see if that changes things.

If not, then the fault may be more serious as it's the ECU/BCM that controls that relay on/off setting.

Thanks for the guidance. I'll try this in the next day or two and revert back.