In terms of noticeability, the HVAC is a 3 compared to the alternator which is a 6 all against the benchmark of the EPB actuator "banshee howl" which is a 10.

 

And to add one more idea to this list of "whine producing items", if the whine is only present when the HVAC system is on (regardless of whether the A/C is on or off), then it may be your blower motor. Easy to replace and not all that expensive, but as the brushes wear and carbon dust coats everything, it can start to emit a whine whenever it is operating.

Houm, I agree with your scale. There is no noise on Earth that will make the hair on the back of your neck stand up like that damn parking actuator screech.

 

No kidding! It's weird (knock wood) but I had it replaced once or twice (I think the first replacement wasn't adjust well so I got a third unit) and it has been good since. I may use it less, but still that was many years ago. Maybe the part was upgraded?

How can the blower motor be in use without the HVAC system being on?

 

It can't. What I was trying to say is that if if the whine is only persistent while the HVAC system is on, and turning the A/C on and off (via the "Econ" button) does not affect the whine, then that particular symptom may be the result of a worn blower unit.

 

Ahhhh....good clarification. I ran that check myself a few years ago. Turned out I was a few pounds low in the HVAC system despite there being no leak. I had it cleaned out and re-filled. The whine didn't go away immediately but it did after a while.

 

When mine was whining last year, the refrigerant was at proper level but they added more oil to lubricate the system. Whine went away...

 

Good info.

I also went out and tested my truck with the same heated windshield test. Same results as the OP. Idle dropped and lugged a bit and then slowly returned to normal. Interior lights dimmed. Didn't roar, but there was a distinct electronic whine, almost like ground feedback. Voltage is sometimes up in the 14-15V range while idling when not driven for a while so I feel like that's still pretty strong.

So either it's normal, or mine is on the way out too. OP, let us know if your new alternator has any effect on this.

 

[QUOTE=

OP, let us know if your new alternator has any effect on this.[/QUOTE]


Will do!


This is indeed, all good info - really liking this forum! When I leave work today I am going to do the 'Econ' check and see if the results are different. I hate shotgunning parts at vehicles, but not knowing much about the maintenance history of my LR3, it will make me feel better. I get a touch of OCD when it comes to my vehicles and maintenance.

 

Ok - I said I would post what effect the new alternator, and I am a man of my word!


So, I was finally able to get back in the shop this last Wednesday to do my alternator swap. On the lift, with the proper tools, it was about a 2 banana job - took about 30 mins. After the swap was done I ran all the button pushing checks that led me to want to change the alternator initially.
The most noticeable and gratifying result was with the windshield heater. Activiating the heater resulted in a negligable dip in rpms, and ZERO alternator howl. Additionally, with the IID gap tool hooked up, the voltage drop was nil - only went down to 13.8 - 13.7 volts.
The AC/HVAC system result was nearly the same - no alternator howl - but the alternator noise gone, I can now confirm that I have a different, lower howl associated with that system running that goes away when I push the ECON button.
So theres that...

 

What was the volt reading off the alternator... I ask because I am getting mine done tomorrow and want to make sure the reman'd unit is functioning the way it should.


Thanx...