Electronic Whining Noise

[tisnart]

I'm getting an electronic sounding whining noise when accelerating and decelerating. At first I thought it was from the radio speakers but it's not.

Anynody else had this?

[Damien89]

Yep mine does it too sometimes, i also thought it was coming from the speakers. So where is it coming from?

[tisnart]

I think I'll book mine into the dealers for a check. Could be normal though I've seen various reasons given for such a sound from Internet searches.

[mentalmechanic]

Mine would do this when the DPF was regenerating. Because the alternator load is engine ECU controlled i'm pretty sure it would put the alternator at max load (the whine), to increase load on the engine, thus helping to increase exhaust temps. Obviously more to it than that for DPF regeneration but this is just to say mine did this for 40k miles and only while the DPF was regenerating. Easiest way to tell when this is occurring is increased idle speed (about 1000 rpm) and cooling fan running. Dealer won't find anything wrong with even if there was!! From my experiences.......