I'm experiencing a whining noise after I turn on the A/C that I'm having trouble locating and also a ticking noise which sounds like it's coming from beneath the passenger seat (LHD car, 2012 4.4 TDV8). Both the whine and the ticking sounds begin roughly one minute after switching on the A/C and last for around ten minutes before dying away. A/C continues to work fine. The ticking begins first and is quite slow but increases in speed as the whine begins. Both noises are independent of the blower which is working normally. If I switch off the A/C before the whine and ticking have stopped, you hear the blower stop immediately but the whine and ticking noise continue for a few seconds longer before stopping.

This video hopefully demonstrates the problem (you may have to turn your volume up).

https://www.youtube.com/watch?v=TnNGCWvf9XU

I had just started the car and then I switch on the A/C. At about 1:00 the ticking begins and at 1:50 the whine begins at which point the ticking sound becomes faster. The whine is quite clear at 2:08 but is otherwise a bit hard to hear over the blower. At 3:40 you can hear how the blower and whine stop independently when I switch the A/C off.

Turning on the cabin air recycling function (either setting) has no affect on the whine or ticking sound (not shown in the video).

Anyone recognise the whine and where it may be coming from? And what is ticking under the seat?

I'd appreciate any help or suggestions you can offer  2012 Vogue 4.4 TDV8 automatic (LHD), Santorini Black
2008 Vogue 3.6 TDV8 automatic (LHD), Java Black

Maybe the ac is low on gas? If the level of gas is low this will cause some hissing noise in the ac system which will change with the speed of the car. I had this symptom on a Peugeot 206 I once owned. Re-gasing the ac system cured the problem.

Martin

watched the video. Clicking nosie is strange. A relais maybe?

Quote:

If the level of gas is low this will cause some hissing noise in the ac system which will change with the speed of the car.

Interesting. If it is the A/C gas level would that be a pump making the whine or a fan or something else? I haven't noticed the whine changing with the speed of the car. It just does it for the first 10 minutes or so after switching on the A/C for the first time since starting the engine.

After 10 minutes or so the whine and ticking noises stop and the A/C continues to work fine. Even if I turn the A/C off and on again the noises don't reappear. It's only after the initial switch-on of the A/C after engine startup.

Something else I should mention, the noises use to also start when I turned on the front seat heater but not the A/C. In this case the whine and ticking noises also started. The dealer has since replaced the seat heater motor (part HHK500060) and now the seat heater no longer causes the whine and ticking noise, only the A/C. 2012 Vogue 4.4 TDV8 automatic (LHD), Santorini Black
2008 Vogue 3.6 TDV8 automatic (LHD), Java Black