Very strange loud banging noise

Trebor · Dec 29, 2020

Hi Everyone. Just wondering if anyone has had this happen ? Got van ( 2015 180 4 motion dsg 38k miles from new ) out of garage yesterday . Everything was fine . Opened driver‘s door to get out and very loud banging noise like the van was being hit hard by a large rubber mallet . I shut the door and it stopped . Opened the door and it started again . Traced noise to the door speaker and saw the gps / radio screen was flashing .Started to look for radio fuse in manual . Started engine fine . After about 5 minutes the banging stopped . I did take a small video on iPhone but can’t see how to attach to this post .
Any ideas much appreciated ?

kurienp · Dec 29, 2020

Trebor said:
Hi Everyone. Just wondering if anyone has had this happen ? Got van ( 2015 180 4 motion dsg 38k miles from new ) out of garage yesterday . Everything was fine . Opened driver‘s door to get out and very loud banging noise like the van was being hit hard by a large rubber mallet . I shut the door and it stopped . Opened the door and it started again . Traced noise to the door speaker and saw the gps / radio screen was flashing .Started to look for radio fuse in manual . Started engine fine . After about 5 minutes the banging stopped . I did take a small video on iPhone but can’t see how to attach to this post .
Any ideas much appreciated ?

Not seen in a Cali, but similar in an old FIAT and was traced to frayed cables short circuiting.

What is the state of the rubber accordion type tubing that connects the door wiring to the body? is that broken or frayed? It is easy to pull it out and check the state of the wires in there? That is a part that moves the most and wires can become brittle in there and crack due to movement.

Could be anywhere else along the wiring as well, but easy to check for an auto audio specialist.

Jabberwocky · Dec 30, 2020

Rodent damage causing shorting?

2into1 · Dec 30, 2020

For the video, you can do a private upload to YouTube (set the privacy to "anyone with link") then post the link here.

Trebor · Dec 30, 2020

Jabberwocky said:
Rodent damage causing shorting?

Hi Jabberwocky .
Yes it did cross my mind but poison in garage and also High pitched pine martin scarer under van . Where do you start looking ?

Jabberwocky · Dec 30, 2020

Difficult to know where to start really. Could be almost anywhere I guess. (I had a problem with a BMW Z4 a few years back. Mice had made a home in the insulation on the gearbox bell housing.)
Did you notice any dash warning lights not going out when engine starts or not coming on at all. You say the GPS/Radio screen was flashing....is that permanent when engine running?
Think I would start with aerial/input and audio output cabling.
Any error codes in the control panel?
Would be good to hear sound.
Have you run a "Carista type" error code check?
You didn't leave anything under the bonnet before you parked your van up? (I'm guessing you didn't but have to ask!)