Rear-View Camera Repair

With the start of winter, one day my rear-view camera stopped working. Before it stopped working, I occasionally got an error:

U007200: Vehicle Communication Bus E (-) shorted to Bus E ()
Eindrahtfehler CAN-Infotainment

I found nothing about this error online. I decided to run guided diagnostics in ODIS Service and see what it would tell me. I started ODIS and it said I needed to check the wiring between two control units:

That is, between the rear-view camera and the multimedia unit. It seemed like nothing complicated, but once I opened the wiring diagram I realized it wasn’t so simple. The CAN Infotainment wires are shielded and run inside the insulation, which makes locating the damaged section very difficult.

I also know that the Audi A3 has a “known issue” — the cables are often damaged at the transition point between the tailgate and the body. I pulled back the corrugated conduit on the right side (where the wiring to the camera runs) and didn’t visually spot any problems.

Given how difficult further diagnosis would be, I put the issue aside — the error was there, but the camera still worked. But by the end of November the camera stopped working altogether, and two more errors joined the first one, giving this final list:

19 CAN Gateway
U007200: Vehicle Communication Bus E (-) shorted to Bus E ()
Eindrahtfehler CAN-Infotainment

U006400: Vehicle Communication Bus E
Bus defekt CAN-Infotainment

5F Electronic Information System
U111100: Function limitation due to missing message
Rear-view camera (0x0B) - function restriction due to communication error - BapErr_retry not successful

At that point I realized I’d have to actually get to the bottom of this error.

I happened to bring up these errors with an Italian guy from a multimedia chat. He told me he’d already run into this problem, and it’s most likely the connector between the camera and the wiring harness. For some reason moisture often builds up inside the tailgate, the connector corrodes, and a short circuit occurs. And if the problem is the connector, that makes fixing it much simpler.

I asked a friend if I could use his garage bay, and together we took apart the trunk lid trim. We looked at this connector and confirmed the Italian was right:

Since I didn’t have a new connector, I decided to clean it with contact cleaner spray. I sprayed it a couple of times, waited a couple of minutes, and wiped it dry with a cloth. I put the connector back together, reconnected everything, and went to check the camera. And it worked!

After clearing the codes by disconnecting and reconnecting the battery, one error related to the camera still remained — the original one:

U007200: Vehicle Communication Bus E (-) shorted to Bus E ()
Eindrahtfehler CAN-Infotainment

But now it was permanent and wouldn’t clear. To fix it, the connector needs to be replaced, and the wires cut and re-pinned/re-crimped. I couldn’t find this connector anywhere locally, so I ordered it from AliExpress. There it’s sold already with short lengths of wire attached.

The part numbers for this connector are:

• 8K0971833
• 8K0971834

For now I’ve only ordered the connectors and they haven’t arrived yet. I’ll update this post once I’ve replaced it.

UPD 29.12.2023

The connector arrived and I replaced it — didn’t help. I kept looking further along the wiring and found that the connector to the camera, and the one on the camera itself, had also corroded away.

There’s no point looking for this connector — I need to order a new camera. Camera ordered.

UPD 01.02.2024

The camera arrived with its handle and wiring, though really I only need the camera with the handle and pigtail.

Replaced the camera, loaded the parameter set, coded and calibrated it. Everything works, no more errors.

Bottom line: the problem was oxidized connectors — for some reason a lot of moisture collects inside the trunk lid, which leads to defects like this.