High pitched 'interference' sound when car is off
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From: London, UK
W212 - E63 AMG
High pitched 'interference' sound when car is off
I was washing my car today and noticed that I kept hearing a high pitch whine (a bit like the sound you get with electrical interference) sound coming from the driverside front of the car (bear in mind that I have a RHD car). I put my ear to the grill and the sound felt like it was pretty close to the grill...almost conveniently near the alternator of just under the intake tube area.....
I've heard this sound before at another time when my car has been 'off', but the last time I heard it was maybe 9 or 10 months ago...ages. The last time it did that, the car was on jackstands overnight from when I was changing my rear discs and in the morning the battery went flat. Today, I made a small adjustment to the passenger front suspension height but the car was on the ground at all times.
I've been seeing the convenience functions message a lot lately on first start up, so I'm going to change over the alternator brush pack this week as a precaution.
I wonder if anybody else has heard this or knows what it might be related to?
I've heard this sound before at another time when my car has been 'off', but the last time I heard it was maybe 9 or 10 months ago...ages. The last time it did that, the car was on jackstands overnight from when I was changing my rear discs and in the morning the battery went flat. Today, I made a small adjustment to the passenger front suspension height but the car was on the ground at all times.
I've been seeing the convenience functions message a lot lately on first start up, so I'm going to change over the alternator brush pack this week as a precaution.
I wonder if anybody else has heard this or knows what it might be related to?
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W212 - E63 AMG
I think whatever it is, is causing my battery drain issues.
I went out for the evening and came back to it after 6 hours, in -2 degree's temps. The car unlocked/fired up but after a few seconds I was greeted with the red battery visit workshop message.
It's nearly 4am now. I wonder if it'll keep draining itself overnight now till the morning/midday when I wake up and end up killing the battery...I'll let you know.
I went out for the evening and came back to it after 6 hours, in -2 degree's temps. The car unlocked/fired up but after a few seconds I was greeted with the red battery visit workshop message.
It's nearly 4am now. I wonder if it'll keep draining itself overnight now till the morning/midday when I wake up and end up killing the battery...I'll let you know.
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W212 - E63 AMG
Went to the car just now (12 hours later) and it was fine in terms of unlocking and starting, but the red battery symbol is still up. I checked the voltage of the main battery while the engine was running and sure enough it was showing 14.00 volts.
Urgh, this car is such a PITA sometimes.
Urgh, this car is such a PITA sometimes.
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W212 - E63 AMG
After some 'net research, it seems like it could well be the small aux battery. My SBC stop feature has been playing up a lot lately and sometimes I don't hear it do that 'brrrrr' sound when I open the driver door, so I'm guessing it's as simple as changing that battery to resolve this problem.
Updates to follow in the week.
Updates to follow in the week.
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2004 E55,1969 300SEL6.3,2011 ML350 BlueTec Diesel,2005 ML400 CDI
You also might want to check the compressor for the AirMatic. That could be what you are hearing (same location in RHD's).
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W212 - E63 AMG
How would I check/know if it's starting to die ^^^
I just changed my aux battery...I used a new Bosch unit which a specialist recommended to me. I did the whole fill procedure etc. Fresh voltage after having let it sit n seal for an hour was 12.58v...I fitted it to the car, fired up the engine...voltage didn't move, DOH! I know though that sometimes this battery won't always charge, right? The red battery message is still on the dash
I guess it's a good thing to change the battery anyway seeing as the old one was stock and the car is 9 years old now. If this cures my SBC stop issues, I'll report back.
Right...hmmm...what else can I change? The main battery was charging fine just now when I fired it up. I'd go for the alternator brush pack next I guess...?
I just changed my aux battery...I used a new Bosch unit which a specialist recommended to me. I did the whole fill procedure etc. Fresh voltage after having let it sit n seal for an hour was 12.58v...I fitted it to the car, fired up the engine...voltage didn't move, DOH! I know though that sometimes this battery won't always charge, right? The red battery message is still on the dash
I guess it's a good thing to change the battery anyway seeing as the old one was stock and the car is 9 years old now. If this cures my SBC stop issues, I'll report back.
Right...hmmm...what else can I change? The main battery was charging fine just now when I fired it up. I'd go for the alternator brush pack next I guess...?
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From: London, UK
W212 - E63 AMG
Been out driving lots this evening and the message is still there, as are the SBC stop issues (I didn't even hear the pump activate when I unlocked the car).
I might take it to my friends workshop to use his Snap On scan tool. Either that or order another aux battery relay.
I might take it to my friends workshop to use his Snap On scan tool. Either that or order another aux battery relay.
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Thread Starter
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W212 - E63 AMG
Ok I had the car scanned for error codes but nothing came up.
I heard (on several occasions today) this high pitched whine sound while the car was unlocked/off and even after it had been unattended for a couple of hours.
The location of the sound is right next to and below the oil filter, on the right side. It looks like it's coming from a little black box with a notched wheel to screw/unscrew. Does that ring true with anyone or shall i take a picture?
I heard (on several occasions today) this high pitched whine sound while the car was unlocked/off and even after it had been unattended for a couple of hours.
The location of the sound is right next to and below the oil filter, on the right side. It looks like it's coming from a little black box with a notched wheel to screw/unscrew. Does that ring true with anyone or shall i take a picture?
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W212 - E63 AMG
lol, I even disconnected the main battery but the sound kept going off. I disconnected the aux battery too and it was still going off!! After about 10 minutes though, it finally stopped.
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I think it is normal. I think it is the keyless go talking to the car (coming out of sleep mode) and preparing the different modules thinking you are about to get in and drive the car.
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From: London, UK
W212 - E63 AMG
Thing is, I've heard it when walking past my car after a few hours but the keys were in the house upstairs...
I'm convinced that my battery drain every 5-6 weeks is because of this.
I'm convinced that my battery drain every 5-6 weeks is because of this.
