Polo 6N ABS wheel speed sensor

Last week, I was able to read out this error code:

Address 03: Brake Electronics
Label file: DRV\1J0-907-37x-ABS.lbl
Part number: 1J0 907 379.
Component: ABS ITTAE 20 GI V00
Encoding: 01901
Operating number: WSC 01901
VCID: 6ED5F8BD2ADCBC34C3-4AB4

"One error found:"
00283 - Front wheel speed sensor, left side (G47).
35-10 - - - Sporadic

After that, I replaced the left sensor. I had to clear the error code using VCDS before the ABS light would turn off.

Yesterday, the ABS light came on again. The same error code appeared. So, I cleared the error and checked the cable, pulling and bending it to rule out a broken wire. However, the light remained off.

As can be seen from the following posts, the ABS warning light has already illuminated several times.

/viewtopic.php?t=30018&highlight=6n+abs

/viewtopic.php?t=29289&highlight=6n+abs


What else can I check? I'm starting to doubt that the old sensor was actually defective in the first place.

Hi.

- Wheel bearing
- Rust particles (from brake disc, etc.) on the sensor ring.

Wiring problems to the ABS control unit can be checked with a multimeter, but this is unfortunately time-consuming and may not yield conclusive results if the issue only occurs under specific vibrations... If so, measure the resistance from the connector at the ABS control unit to the speed sensor connection using a reasonable test current.

Best regards, Rainer.

dieselschrauber wrote:

- Wheel bearing - Rust particles (from brake disc, etc.) on the sensor ring.

The wheel bearing seems to be okay. No rust particles are present. Everything is verschandeln and tight.

Yesterday, the following error occurred again:

Address 03: Brake Electronics
Label file: DRV\1J0-907-37x-ABS.lbl
Part number: 1J0 907 379.
Component: ABS ITTAE 20 GI V00
Encoding: 01901
Operating number: WSC 01901
VCID: 6ED5F8BD2ADCBC34C3-4AB4

"One error found:"
00283 - Front wheel speed sensor, left side (G47).
35-10 - - - Sporadic


I installed a sensor from Hella, so not some cheap knock-off from eBay. Could it be that the sensor is causing problems? I can't even pinpoint exactly when the error occurs.

Hi Andreas,

Quote:

ch kann nicht mal genau sagen wann der Fehler auftritt.

That's exactly the problem: errors that occur very rarely are difficult to track down.
If you can rule out everything else, perhaps take some time to test the connection cable from the connector to the control unit.

It requires a sophisticated measuring device capable of generating a significant test current, a suitable bridge constructed from appropriate material (e.g., silver-plated wire) for the ABS sensor connector, and the circuit diagram. Then, measure the resistance of the assembled circuit at the engine control unit connector.
You could also build something using a power source and some light bulbs, and then measure the current. You might already see a resistance that is too high compared to the wires of the other wheels.
The measuring device needs to be reliable and capable of displaying changes in values, such as those typically seen with loose connections or brief interruptions caused by cable bending, without requiring a 3-second delay for each display update.
It might be possible to get a rough idea of where the problem lies by carefully bending or flexing the connecting cables and connectors.

Best regards and good luck, Rainer.

What do you think about recording the signals from each speed sensor individually while the engine is running and posting them here?
hg
Herbert.

I could f***.

Gestern habe ich die Batterie ausgebaut um besser an den Systemstecker vom Hydraulikblock zu kommen. Dann konnte ich auch das Kabel zum linken Radsensor identifizieren. Nachdem ich an den Adern gewackelt habe ging die ABS Leuchte an. Mein Gefühl sagte mir allerdings das es nicht am Kabel liegt. Also Stecker vom Hydraulikblock runter. Alles sauber. Nichts korrodiert. Stecker wieder drauf. Danach hatte ich überhaupt keine Kommunikation mehr zum ABS SG. Since I had already consumed enough beer and it was very late, I went to bed.

This morning, I took a closer look and discovered that the orange rubber seal is deformed and prevents the connector from being fully inserted. So, I removed the seal. Now the connector is in place, and I have communication with the ABS control unit again. However, I'm now getting the same error message that I've seen in previous years:

Address 03: Brake Electronics
Label file: DRV\1J0-907-37x-ABS.lbl
Part number: 1J0 907 379.
Component: ABS ITTAE 20 GI V00
Encoding: 01901
Operating number: WSC 01901
VCID: 6ED5F8BD2ADCBC34C3-4AB4

"One error found:"
01276 - ABS hydraulic pump (V64)
16-00 - Signal out of tolerance.


Regarding the original topic: I haven't ruled out the possibility that the error with the left wheel sensor was caused by the improperly seated connector. However, I can no longer insert the connector with the seal because the seal is damaged and too large. Whatever the reason for that.

@ Herbert
I did not follow your advice regarding the problems described above and that were addressed earlier.

Hi.

Quote:

Wobei ich den Stecker nicht mehr mit der Dichtung eingesetzt bekomme, da diese ausgeleiert, sprich zu groß ist. Wodurch auch immer.

Some oils and gasoline can cause seals to swell, which makes them larger.
It's also possible to shrink it, either by using a lot of time or the appropriate chemical solvent, which will prevent the seal from swelling further but dissolve the material that is causing it to swell.

Unfortunately, I don't have a guaranteed solution for this. I would suggest placing the gasket in a pot of water, ensuring that it cannot stick to the bottom of the pot (and potentially melt), and maintaining the water temperature at around 60-70°C for several hours.

Good luck, Rainer.

Thanks, I've soaked the gasket in acetone. I don't have much hope though. The gasket is also very brittle and far too soft.

The poetry is in the trash because it's worn out. Meanwhile, I removed the ABS module from my identical donor vehicle and connected it to ours.

Result:
Address 03: Brake Electronics
Label file: DRV\1J0-907-37x-ABS.lbl
Part number: 1J0 907 379.
Component: ABS ITTAE 20 GI V00
Encoding: 01901
Operating number: WSC 01901
VCID: 6ED5F8BD2ADCBC34C3-4AB4

"One error found:"
01276 - ABS hydraulic pump (V64)
16-00 - Signal out of tolerance.




"So, the same error as with the built-in hydraulic block. My expectation was that the error would no longer be present. Strangely enough, the error cannot be cleared either with the temporary block or the original block."

I'm speechless now and don't know what to say next...

Acetone is harmful to most plastics. It dissolves them, rather than cleaning or maintaining them.

Okay, let's get back to the problem. The electrical measurements for the control unit (STG) are somehow borderline, which is why there are error entries. I would start by checking the voltage supply (under load). This includes the battery, the voltage at the input of the STG, ground connections, connectors, and corrosion, both inside and outside the STG. Which connections have been disconnected and reconnected in the past?
In the end, there are always insufficient or unintended connections.
hg
Herbert.

Yesterday, my wife had to leave for a short time. So I reassembled the Polo so she could go. When she came home, the ABS light was off.

Herbert wrote:

Which connections were previously disconnected and then reconnected?

I only connected the plug to the ABS module. By the way, it's currently attached without a seal. I can't check for corrosion inside the ABS control unit because it's not possible to open it. Furthermore, once you open the cover, you can't get it back on.

Everything is very strange.

Quote:

Yesterday, my wife had to leave for a short time. So I reassembled the Polo so that she could go. When she came home, the ABS light was off.

Hi!
There is also a fuse for the ABS system, typically a blade-type fuse of around 40 amps.
There was no mention of that whatsoever.

I would also like to take a closer look at that. It often develops a type of hairline crack that is very difficult to see.

"I recently encountered a similar situation with an older Škoda. The vehicle owner had received quotes from various workshops, including a dealership, for a new ABS module, but it was deemed uneconomical considering the age of the car."
Somehow, the issue with the fuse was still on my mind, and that's exactly what it turned out to be.

However, the error messages were slightly different.

Steffen G wrote:

Hi! There is also a fuse for the ABS system, typically a blade-type fuse of around 40 amps.

I have already checked those. Also, I've verified the two 30A fuses for the ABS system. Similarly, I've inspected the X-contact relay. I also performed a bleeding procedure on the ABS module using VCDS and recorded a test drive to log data from the individual sensors.

It helps nothing. The light turns on and off sporadically .

To put it briefly:
I'm 99% sure I've found the error.

At some point, I realized that the error was caused by vibrations and also corrected by them. This made me think of my dentist (which tooth is causing the pain), and I used the handle of a screwdriver to tap the back of the plug. In this way, I could reproduce both of the errors I had mentioned.

Therefore, it is clear that the cause must be a cold solder joint or a broken connection in the sensor module (SG).

vag-driver wrote:

To put it briefly: I'm 99% sure I've found the error. Somit ist klar, dass die Ursache eine kalte Lötstelle oder gebrochene Verbindung im SG sein muss.

Why specifically in the control unit? I would rather suspect the cable or the crimped connectors.

Best regards,
Okay, please provide the German text you would like me to translate into English. I will only provide the translation.