Parking Assist Fails: No Function with New Sensor

Hello everyone,

I hope someone can help me.
The front left parking sensor on my Audi A6 4B (year 2003) is not working.
I installed a new one, and it worked for a few days, but then it stopped working again.
I then installed a new one, but it didn't work at all.
I then tried to measure the voltage through the connector, but without success; there were no 12V on any of the pins.
Neither of the large connectors for all the sensors in the front bumper has any voltage (12 volts) present anywhere.

Of course, the parking distance control (PDC) was activated during the check, and the other three sensors were also working.

There must be power running through it.

How can I check that? I don't think both of the new sensors are faulty.

Greetings.

A broken cable, corrosion in a connector, or another faulty component could be causing your parking distance control (PDC) to switch off.

All other sensors are functioning correctly.
How can I test the cables to check for potential breaks or faults?
As I said, there are no 12V connections anywhere .

What information is stored in the error memory?

I don't remember the exact description, but it triggers an error related to the front left outer sensor.

transambandit wrote:

I don't remember the exact description, but it causes an error with the sensor on the front left outside.

It's interesting to know which message appears with the new sensor.

I'll read it again. But the last message already included the first update.

I would start by swapping the sensors on the right and left sides.
If the error persists, it means you either bought the sensors too cheaply or they are defective.

If the error persists, you have a problem with either the wiring or the control unit.
In this case, you could temporarily swap the left and right output cables directly at the control unit to see if the problem lies with the control unit itself or the wiring. (The display will be inverted during this test.)

Greetings.
Sure.

Here is the translation of the text from German to English:

"Guste" means "gust" in English. It can also be used as a verb, meaning "to gust."

Can you tell me where the control unit is located?

transambandit wrote:

Can you tell me where the control unit is located?

In the trunk, on the left side, behind the side panel.
Pinout of the 12-pin brown connector.
VL = 5
VL Middle = 6
VR Middle = 7
VR = 8

Pinout of the 12-pin black connector.
HL = 5
HL Middle = 3
HR Middle = 2
HR = 4

Great, thank you very much .
That helps me a lot for now!