ABS Module to Wheel speed sensor wiring harness

[S4_SH1640]

Having some trouble finding the issue with my abs wheel sensor on the Right Front side.

VCDS cannot pull a reading on this sensor while the other 3 sides are showing resistance and working great.

I replaced the sensor and still nothing. When I delete the code, it immediately shows up again.
Did some research and came across this TSB : https://static.nhtsa.gov/odi/tsbs/20...54858-2629.pdf

Not sure if this is my issue but wanted to check if you guys had wiring harness issues before?

Also, is there a way to check with vagcom if there is power going from ABS module to wheel sensor.
Any way to check with vagcom if the ABS module is faulty?

Thanks in advance.

[Smac770]

If I wanted to validate circuit connectivity to the wheel speed sensor, I'd pop the plug off the ABS/ESP control module (the big plug on the brake hydraulic unit next to the coolant reservoir) and check continuity of the following:

T38a/22 to G47 (front left) pin 1 - yellow wire
T38a/34 to G47 (front left) pin 2 - red wire
T38a/33 to G46 (rear left) pin 1 - white wire
T38a/20 to G46 (rear left) pin 2 - black wire
T38a/18 to G45 (front right) pin 1 - green wire
T38a/6 to G45 (front right) pin 2 - black wire
T38a/31 to G44 (rear right) pin 1 - yellow wire
T38a/20 to G44 (rear right) pin 2 - black wire

Issues with the joins of the wheel well wiring to the main harness are not unheard of.

If I wanted to test the sensor itself, I'd swap it with the one from the opposite corner of the car. So swap front right with rear left (opposite corners use the same sensor).

If the wiring rings out good and the sensor works fine in the opposite corner, that would seem to leave just the ABS/ESP control module. Which is not the cheap conclusion.

[S4_SH1640]

If I wanted to validate circuit connectivity to the wheel speed sensor, I'd pop the plug off the ABS/ESP control module (the big plug on the brake hydraulic unit next to the coolant reservoir, and check continuity of the following:

T38a/22 to G47 (front left) pin 1 - yellow wire
T38a/34 to G47 (front left) pin 2 - red wire
T38a/33 to G46 (rear left) pin 1 - white wire
T38a/20 to G46 (rear left) pin 2 - black wire
T38a/18 to G45 (front right) pin 1 - green wire
T38a/6 to G45 (front right) pin 2 - black wire
T38a/31 to G44 (rear right) pin 1 - yellow wire
T38a/20 to G44 (rear right) pin 2 - black wire

Issues with the joins of the wheel well wiring to the main harness is not unheard of.

If I wanted to test the sensor itself, I'd swap it with the one from the opposite corner of the car. So swap front right with rear left (opposite corners use the same sensor).

If the wiring rings out good and the sensor works fine in the opposite corner, that would seem to leave just the ABS/ESP control module. Which is not the cheap conclusion.

Smac770 Thank you. I will look into this tomorrow. I appreciate the input.

[S4_SH1640]

Image1615122200.642001.jpgImage1615122207.411810.jpgImage1615122217.662333.jpgImage1615122225.493477.jpg

Thanks for the help. I was able to find an old repair job on the wiring and it looks like this was the cause.



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