TOEd
Posts: 93
Joined: Sat Mar 05, 2016 5:15 am
Location: Toronto Ontario Canada

Buzzing from REx cooling fan

Mon Dec 04, 2017 8:32 am

Has anyone had a REx cooling fan buzz? After 38,000 km (10,000 km on REx) the cooling fan has started to emit an annoying buzzing sound. I haven't crawled under there yet so it may be an easy fix. I hate the idea of bringing it to the dealer because it will waste half a day and last time they spun the driver mirror 180 degrees from normal when they took it through car wash. Their fix was to manually crank the mirror back into position and assure me this was normal and that no damage was done.

tobiassej
Posts: 30
Joined: Sun Aug 09, 2015 6:14 am
Location: Denmark

Re: Buzzing from REx cooling fan

Sat Jan 06, 2018 1:24 pm

I might have the same issue. However I have a BEV (not REX) and it's winter here (Denmark, 0-5 Celcius).
I get a rumbling noise from both front and back of the car. The rumbling sound is gone when I turn heating off.
It's especially a problem when preheating the car or standing still.
People ask me if the car has a problem.
I'm taking it to the dealer next week but they had no idea ahead of the service.

Anyone has a hunch?

jadnashuanh
Posts: 4090
Joined: Thu May 22, 2014 2:07 pm
Location: Nashua, NH USA

Re: Buzzing from REx cooling fan

Sat Jan 06, 2018 7:43 pm

The heat pump can get loud. Not sure that is an indication of a problem. Not sure how to separate that noise from the coolant circulator in the batteries.
Jim DeBruycker
2011 535i x-drive GT, 2014 i3 BEV

RockSalt
Posts: 6
Joined: Fri Jan 12, 2018 12:28 pm

Re: Buzzing from REx cooling fan

Fri Jan 12, 2018 12:35 pm

I have the same issue reported by tobiassej, and just scheduled an appt for next week. When driving over 30mph with the heating on, after several minutes a loud buzzing noise like a rattling bathroom fan starts. Each time the vehicle slows below 30mph to stop, the noise subsides. when the vehicle speeds back up, the noise returns. If while driving with the heat on and the noise present, I shut off the heating, the noise goes away. If I then turn the heat back on, after a minute or less the noise returns. Based on other reading I suspect this is the compressor for the coolant system that cools the batteries, which would presumably be under load when driving over 30mph with the heat on. However it does not make sense that the system would run continuously as it does when driving with the heat on or be that noisy.

jadnashuanh
Posts: 4090
Joined: Thu May 22, 2014 2:07 pm
Location: Nashua, NH USA

Re: Buzzing from REx cooling fan

Fri Jan 12, 2018 5:03 pm

The REx, unlike the BEV, does not have a heat pump. The BEV's heat pump is a bit noisy from the outside, but not significant inside the vehicle. This time of year (at least in the northern hemisphere), excessive heat is probably not an issue. I think the batteries, if they did need cooling, could just use the pump and radiator.
Jim DeBruycker
2011 535i x-drive GT, 2014 i3 BEV

RockSalt
Posts: 6
Joined: Fri Jan 12, 2018 12:28 pm

Re: Buzzing from REx cooling fan

Fri Jan 19, 2018 7:15 pm

RockSalt wrote:I have the same issue reported by tobiassej, and just scheduled an appt for next week. When driving over 30mph with the heating on, after several minutes a loud buzzing noise like a rattling bathroom fan starts. Each time the vehicle slows below 30mph to stop, the noise subsides. when the vehicle speeds back up, the noise returns. If while driving with the heat on and the noise present, I shut off the heating, the noise goes away. If I then turn the heat back on, after a minute or less the noise returns. Based on other reading I suspect this is the compressor for the coolant system that cools the batteries, which would presumably be under load when driving over 30mph with the heat on. However it does not make sense that the system would run continuously as it does when driving with the heat on or be that noisy.


Update: The shop had the car for 2 days, and did several test drives. Both a technician and a shop manager verified the noise and confirmed my suspicion that it was coming from the coolant system compressor. They opened the car and found that the compressor was literally disintegrating, the process spewing metal fragments into the cooling lines. So now I get to wait 2 weeks for parts from Germany, and the dealership needs to not only replace the compressor, but they need to flush all of the cooling lines, including the lines that run through the battery pack, which they need to remove from the vehicle to do. Wow. All from an annoying noise! Also, anecdotally, I have noticed my post full charge mileage prediction decreasing, and when driving the predicted available mileage decreases faster than I am able to drive, i.e. 25 mile range prediction nearly leaves me stranded after 16 miles...I hope that what appears to be a failing cooling compressor is what was also contributing to reduced mileage, as the battery was not being properly cooled? Hopefully once the compressor is fixed, I get my range back too.

tobiassej
Posts: 30
Joined: Sun Aug 09, 2015 6:14 am
Location: Denmark

Re: Buzzing from REx cooling fan

Wed Feb 07, 2018 12:16 pm

They are replacing the water pump tomorrow - hope it works.

price 760 Euro = 945 US$ incl finding the noise problem.

Hope it works.

First repair that I have to pay myself after 75.000 km

tobiassej
Posts: 30
Joined: Sun Aug 09, 2015 6:14 am
Location: Denmark

Re: Buzzing from REx cooling fan

Thu Feb 08, 2018 12:49 pm

Picked up the car today after water pump exchange and a 945$ bill. The car started doing the same noise again after 1-2 km of driving.

Called the dealer right away and first thing he said was that they still had the old pump:/

So were are back to zero - the water pump was not the problem. It's a noise from the back of the car that stops if heating is turned of. It can appear while fast charging the car as well. Looks like I need to take it back to BMW....

RockSalt
Posts: 6
Joined: Fri Jan 12, 2018 12:28 pm

Re: Buzzing from REx cooling fan

Fri Feb 09, 2018 10:45 am

RockSalt wrote:
RockSalt wrote:I have the same issue reported by tobiassej, and just scheduled an appt for next week. When driving over 30mph with the heating on, after several minutes a loud buzzing noise like a rattling bathroom fan starts. Each time the vehicle slows below 30mph to stop, the noise subsides. when the vehicle speeds back up, the noise returns. If while driving with the heat on and the noise present, I shut off the heating, the noise goes away. If I then turn the heat back on, after a minute or less the noise returns. Based on other reading I suspect this is the compressor for the coolant system that cools the batteries, which would presumably be under load when driving over 30mph with the heat on. However it does not make sense that the system would run continuously as it does when driving with the heat on or be that noisy.


Update: The shop had the car for 2 days, and did several test drives. Both a technician and a shop manager verified the noise and confirmed my suspicion that it was coming from the coolant system compressor. They opened the car and found that the compressor was literally disintegrating, the process spewing metal fragments into the cooling lines. So now I get to wait 2 weeks for parts from Germany, and the dealership needs to not only replace the compressor, but they need to flush all of the cooling lines, including the lines that run through the battery pack, which they need to remove from the vehicle to do. Wow. All from an annoying noise! Also, anecdotally, I have noticed my post full charge mileage prediction decreasing, and when driving the predicted available mileage decreases faster than I am able to drive, i.e. 25 mile range prediction nearly leaves me stranded after 16 miles...I hope that what appears to be a failing cooling compressor is what was also contributing to reduced mileage, as the battery was not being properly cooled? Hopefully once the compressor is fixed, I get my range back too.



Parts are on backorder from Germany, car is at Dealer for the next few weeks...will update once repair is done

RockSalt
Posts: 6
Joined: Fri Jan 12, 2018 12:28 pm

Re: Buzzing from REx cooling fan

Fri Feb 09, 2018 10:52 am

tobiassej wrote: It's a noise from the back of the car that stops if heating is turned of. It can appear while fast charging the car as well. Looks like I need to take it back to BMW....


This really sounds like the same problem I have, have them check the compressor that manages the cooling for the battery pack and A/C

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