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Discussion Starter · #1 ·
Today I took my car for a quick ride nothing unusual until I got home and parked it. I was standing in my garage and I could hear this noise and couldn’t figure out where it was coming from. I then went to lock my car with the key fob and nothing. I tried a couple more times...nothing. I went to open the door and close it then tried again and it started right up. I’m thinking the battery on the key fob. I tried my other key fob....it would not start. I repeated opening the door and closing it and it started again. Wtf!! I went back out side after I ate and I can still hear this high pitches whining noise coming from the engine. I lifted the hood and stuck my phone into the front drivers side and here is the clip. It’s not as loud as it sounds in the video because I have the volume up. My worried is something going on that’s drawing my Battery or is the remote start an issue in the module. Idk! Anyone have any ideas. Afraid to leave my car in the garage now.
Anyone know how to post a video!? I can let you guys hear it.
 

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Discussion Starter · #3 ·
 

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Discussion Starter · #4 ·
The sound has since stopped. Again the car was Completely off. Don’t know if if the starter module is on the brink: it obviously affected the key fob because I could not use either one until I opened up the car door. Mileage is 24000KM/15000miles.
 

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My suspicion is it could be related to the AC compressor.
 

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Discussion Starter · #6 · (Edited)
My suspicion is it could be related to the AC compressor.
After I posted, I read there were quite a few who have had this problem. No one seems to have a definitive answer on it. The sound is right at front drivers side. Most who have had it was after the car was wet. My car still to this day hasn’t seen rain. I’ve never noticed it washing it either. One guy even had his U connect and battery changed. His tech said the U Connect wasn’t shutting down properly. I’m going to drop by the dealership with the video or a maybe the car will replicate what it did today.
 

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There are quite a few threads on this noise over that past couple of years (I participated in some of the discussions). BTW the AC compressor is on the front, driver side of the engine which is again why I think it might be the variable displacement AC valve. Like I showed there are some chevy vehicles that have a similar noise that is attributed to the AC valve.

Next time you hear the noise try putting your phone up to the AC compress to see if you can record any noises coming from it.
 

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Discussion Starter · #8 ·
I’ll try that tomorrow. You think the valve itself is faulty or just doing its job? Most guys who have had this don’t seem to have any performance issues with their cars. What your saying seems logical. The compressor should only run if the air is on and the defrost is on? If that’s the case, I wasn’t running either during my drive.
After hearing the sound I was worried about whatever it is killing my battery. Why is it affecting my key fob...both key fobs? The car would not start at all not unlock or lock the doors. Something isn’t connecting. As soon as I opened the drivers door, no problem starting. All these cars have that hum sound as soon as you unlock the doors and the head lights come on.
im wondering if there is a module that wasn’t shutting down?
 

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If your climate control is on auto it is possible the AC compress may cycle once in a while. In fact, I think the compressor cycles every so often just to keep the system lubricated. As for the valve being faulty, I think it is more of a design flaw but I don't really know. As for your keyfob issues...when was the last time you replaced the fob batteries? On my 2015 both fobs required battery replacement last year. I don't think every car exhibited the buzz upon door unlock. There was one member that had the headunit replaced and stated the noise went away but what I don't understand is the headunit is inside the cabin and the noise seems to be coming from outside under the hood (at least that is what folks claim). BTW I used to hear a roadrunner type beep whenever my car was cooling down. I thought it was something electrical but it turned out to be the coolant bottle cap which is another reason why I think the noise is from the AC and not a module. Hopefully you can finally put to rest what is causing this buzz. If it is very consistent I would have the phone handy to record the AC compressor. If that ain't it then my next guess would be the OCV (VVT valve) as it uses PWM signal when activated. I have a hard time believing it is the headunit because there is nothing in it to cause an audible noise.
 

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Discussion Starter · #10 ·
If your climate control is on auto it is possible the AC compress may cycle once in a while. In fact, I think the compressor cycles every so often just to keep the system lubricated. As for the valve being faulty, I think it is more of a design flaw but I don't really know. As for your keyfob issues...when was the last time you replaced the fob batteries? On my 2015 both fobs required battery replacement last year. I don't think every car exhibited the buzz upon door unlock. There was one member that had the headunit replaced and stated the noise went away but what I don't understand is the headunit is inside the cabin and the noise seems to be coming from outside under the hood (at least that is what folks claim). BTW I used to hear a roadrunner type beep whenever my car was cooling down. I thought it was something electrical but it turned out to be the coolant bottle cap which is another reason why I think the noise is from the AC and not a module. Hopefully you can finally put to rest what is causing this buzz. If it is very consistent I would have the phone handy to record the AC compressor. If that ain't it then my next guess would be the OCV (VVT valve) as it uses PWM signal when activated. I have a hard time believing it is the headunit because there is nothing in it to cause an audible noise.
The key Fob batteries are fine. The one fob has never been used. As I said, as soon as I open the door it acts like a reset for whatever reason. Key fobs work no problem with every push of any button no hesitations. The thread I read on the head unit his tech said that his u connect wasn’t shutting down right. That high pitch sound when u unlock your car I believe is the headlights. As soon as you power up the car without starting it or open a door u can clearly hear it from your drivers door or even the rear of the car. I’m going to tinker around with it before I hit the dealership sometime tomorrow to talk to a tech. I still can’t believe no one has narrowed it down with the amount who have complained about it. Sucks to have a low mileage car with the warranty about to expire. I was thinking of purchasing the extended warranty before the 3 year one expires. Wonder if it’s really worth it although it’s helped me on my 15 Jeep Sahara.
 

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The reason I brought up the batteries in the fob is because I did not get any warning, they just started acting up. If you find the source of the buzz...your next task will be to identify what causes the hemi tick. ;)
 

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I had a similar issue.

Started working without issue and hasn't given me any crap since.
 

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do you have HIDs in your car? that also sounds like what the HID or an LED ballast sounds like when they are being powered up.
 

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I didn't hear anything from my car.

But the keyfobs were randomly dead.
 

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Discussion Starter · #17 ·

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It actually sounds the same just his is doing continually. Like all others no one seems to pin point only with a guess.
Yeah, turns out that guy had the problem come back...so I guess the AC compressor valve may not be the issue. BTW last night I had my hood open (checked the oil, engine was still warm) and I started to hear a very faint shreeking noise...turns out it is coming from the coolant tank cap again.

If I heard the noise you are hearing I would also try an disconnect the headlight connects...that will rule out the ballasts.
 

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Discussion Starter · #19 ·
I took the car in today but couldn’t replicate the sound. So I played it for the tech and actually their head mechanic who happened to be standing an earshot from us come over to listen. Both have never heard the noise. The mechanic said its hard to pin point it if he doesn’t hear it. He said he’s been building engines since he was a kid and never came across it. I hate To admit it but I was going though my message Center on my dash and it said Key fob battery low. I feel like an ass after thinking the battery was ok, Lol! So maybe just maybe could it be that the car wasn’t communicating with the keyfob? Maybe it has something to do with the key fob And starter module? I washed my car and the noise hasn’t come back considering most have the issue after washing their cars. oh well! Maybe one of those phantom issues that will just be.
 

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Yeah, turns out that guy had the problem come back...so I guess the AC compressor valve may not be the issue. BTW last night I had my hood open (checked the oil, engine was still warm) and I started to hear a very faint shreeking noise...turns out it is coming from the coolant tank cap again.

If I heard the noise you are hearing I would also try an disconnect the headlight connects...that will rule out the ballasts.
Interesting. Is the cap venting pressure or allowing air into the tank as the coolant cools down?
 
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