This one is a thinker, though.

The problem has changed over the past month (gotten more severe). It used to be that randomly, about twice every 3 days, the ABS/ESP malfunctions would appear, always together, and I would lose cruise control (no response from the car when the stick is used). When the engine was shut off and turned back on, after the car moved forward a few meters both would go away for a while. While driving, they can appear at literally any point - while stopped at a light, while driving, or even while cruising down a straight flat highway with cruise control on (yes, the cruise control beeps and shuts off when that happens). Over the past month it's gotten worse, to the point where after doing the engine restart the malfunctions will return in just a few kilometers, if not less (once it took 2 blocks). I've also noticed that often they return on their own, without the car starting or moving, overnight or during a work day. That means that just about every morning lately they're there waiting for me when I start the car to drive to work.

I get fault codes:
U140A - The right front wheel rpm signal sent from the traction system via the CAN bus is implausible.
and
P1425 - Wheel speed signal implausible
and one more code which is basically the ESP malfunctioning because there's no ABS/speed info
All 3 descriptions will be attached as images

I've done the following:
- erased all codes completely - seems to keep the problem at bay for at most a day
- did the steering wheel right to left reset thing - absolutely nothing
- tried 2 different new ABS speed sensors on the front right - no effect
- checked brake light switch - don't have an electric one behind the gas pedal, my model seems to have the pressure one connected to the main brake cylinder
- checked and monitored the battery voltage - solid 12.5V static, 14.2V when driving. Using a load test tool only went down to about 11V
- disconnected the battery and held the brake pedal for a minute - no effect

Any ideas?

 

what is the fault code in the ESP or traction system? can u read live data from ESP! if you can have a look at wheel speeds while you drive off. see if the wheel speeds are much the same in a straight line. Are the wheel/tyre sizes all correct?

 

The code about the ESP is in the attachments in my first post. I don't know if I can, but I'll try to look at the wheel speeds while driving. The current wheel sizes are all 225/45R17, but the problem used to happen when I had the stock 205/55R16 ones.

The thing that I just can't explain is how the codes can return overnight, while the car is sitting there, appearing before it even moves...