W211 ABS EPS defective fixed, but still malfunction

[Maestro1658]

Hi all,

my S211/W211 E240 -2004 started to show these in autumn, on and off:

ABS, EPS defective, Service brakes. Later became constant. On top of that Brake wear in Winter time.

Autel MD802 showed P0500A, left rear speed sensor/wiring fault.

Changed it, noticed a damaged ABS/ reluctor ring, changed that too.

Brake pads are good, changed last year.

I erased trouble codes, but it all comes back when turning ignition on.

Any ideas anyone?

Thx

 

[4life211]

It might be sbc unit defective

 

[saff]

could be brake light switch

 

[AMGeed]

As above, a cheap fix is replacing the Brake light switch for under £20. That is often the reason for the ESP light.
What is the exact message you see since you changed the speed sensor (OEM I hope) and the reluctor ring?

Here is a quick How to for the brake switch

https://www.youtube.com/watch?v=Q3-5H1LfBls

 

[Maestro1658]

Thx for the tips, I considered the brake switch, though it show no trouble code.

I bought a "A.B.S CLS500" OEM sensor. ABS ring noname brand OEM.
After replacing, diagnostic tool said:

"L6/3 left rear speed sensor, check sensor/wiring"

My dad took the car to a mechanic yesterday, same trouble code. They jacked the car up, turned front wheel which showed normal output on diagnostic tool. But when turning left rear wheel no output at all.

I lean toward a fault in sensor connection.

 

[Maestro1658]

Solution:

The mechanic tried all connections and wires. Nothing. Then he re-calibrated the ABS pump. Then suddenly the new abs-sensor was recognized...

Surprise for me. But it's fixed.