[AnthBech]

Hi All,

Not sure if there are any threads with the same issue, if you know of any, be sure to reply with a link!

I have a 2007 BMW 323i and the Brake/ABS/DSC lights had been coming on intermittently for a couple of months. Recently went on permanently for about a month. Scanned the car with my Autel Scanner and it showed the following codes:
ABS-DSC Dynamic Stability Control:
- 5DF0 - DSC: Hydraulic Pump Unit: Pump Motor (Error Not Present)
- 5DF1 - DSC: Hydraulic Pump Unit: Pump Motor connector faulty (Error Not Present)
- 5DE0 - DSC: Brake-pad wear: Plausibility, front axle (Error Present)

Took the car to my mechanic about a 2 weeks ago, he scanned it with a SnapOn Scanner only to get the same readings, he cleared them then told me to go home, bypass the brake wear sensor and reset the service warning for my brakes using my own scanner. A few days ago i done this, bypassed the sensor by crossing the wires, reset all my service intervals and rescanned the car. Took the car for a short drive and errors stayed the same only this time with:

EHS GM6 transmission control:
- 578E - EGS: Gearbox Oil: wear (Error Present)

Took the car back home, connected my scanner and reset the codes then went through trying to see if i can see the live readings of the ABS modules and Transmission modules using my scanner, then i realised that my rear right speed sensor gets a "No Value" reading. Re-erased all codes and then took the car for a drive again and the warning lights all turned off.

Today i woke up, warmed my car up, then as soon as i took off, the lights returned.

Has anyone else had similar issues? any recommendations?

This evening i will run the vehicle on the scanner again and see if anything new has arised but i am unsure what the issue can be at this stage. I will try and replace/clean the rear right speed sensor this week incase that is what is tripping the ABS system.

[gbalthrop]

Originally Posted by AnthBech

... 2007 BMW 323i and the Brake/ABS/DSC lights had been coming on intermittently for a couple of months... Scanned the car with my Autel Scanner and it showed the following codes:
ABS-DSC Dynamic Stability Control:
- 5DF0 - DSC: Hydraulic Pump Unit: Pump Motor (Error Not Present); - 5DF1 - DSC: Hydraulic Pump Unit: Pump Motor connector faulty (Error Not Present); - 5DE0 - DSC: Brake-pad wear: Plausibility, front axle (Error Present) [NONE of those codes have anything to do with the 3 warning lights being on at the time the codes were read. ABS Pump Motor/ Connector faults were NOT PRESENT when read, and Brake Pad Wear, does NOT cause ABS/DSC warning lights. There SHOULD be a Fault Code present for Wheel Speed Sensor signal error -- see below]

A few days ago i bypassed the sensor by crossing the wires, reset all my service intervals and rescanned the car. Took the car for a short drive and errors stayed the same only this time with: EHS GM6 transmission control: - 578E - EGS: Gearbox Oil: wear (Error Present) [THAT "578E" Fault Code appears on vehicles with GM6 AT when Transmission Fluid Quality (or miles/km since reset) reaches ~ 200,000 km. It does NOT cause ANY warning light on the Instrument Cluster, and has NOTHING to do with your warning lights. Replace Transmission fluid and Filter when able. NOT an emergency.]

Took the car back home, connected my scanner and reset the codes then went through trying to see if i can see the live readings of the ABS modules and Transmission modules using my scanner, then i realised that my rear right speed sensor gets a "No Value" reading. Re-erased all codes and then took the car for a drive again and the warning lights all turned off. Today i woke up, warmed my car up, then as soon as i took off, the lights returned...

The three lights (Brake, ABS, DSC) are MOST OFTEN caused by a bad signal from one of the four Wheel Speed Sensors. There SHOULD be a fault code saved in the DSC Module Memory which identifies WHICH Sensor. As you have discovered, LIVE DATA or reading Parameters, in this case the INPUT from each of the four Wheel Speed Sensors to the DSC, is the best way to confirm a particular fault.

A Wheel Speed Sensor Signal tells the DSC (1) Wheel Speed; AND (2) Direction of rotation: a) forward, b) rearward, c) stationary. I presume from your description, you are seeing NO signal from RR sensor and other 3 "Stationary" (Steht) when vehicle is NOT moving? You can also check Freeze Frame Data or Fault Details, and see vehicle mileage/km when the fault code was saved, as well as whether the fault is currently present, or if it would set a Warning Light.

If you have NO wheel speed sensor signal from the RR wheel, that may be due to:
1) Sensor Connector in wheel well Loose, Corroded, Damaged; Wiring Fault in associated wiring;
2) Dirty "Tone Ring" or Toothed Reluctor which is supposed to turn with the axle shaft and whose teeth are "read" by the Sensor to determine speed;
3) Broken Tone Ring due to rust beneath causing the Tone Ring to break and rotate freely, or not at all, even though axle is rotating. This is a frequent occurrence on other vehicles -- NOT sure about E9x;
4) Improper air gap between Tone Ring & Sensor;
5) Bad Sensor itself (perhaps least likely).

Here are the TIS circuit diagrams for the DSC Module to which the four Wheel Speed Sensors are connected, the first for 2007 Models built BEFORE 3/1/2007, and the 2nd for LATE 2007 models built AFTER 3/1/2007. "B3" is the Rear Right Wheel Speed Sensor:
https://www.newtis.info/tisv2/a/en/e...ol-dsc/eukxvG6
https://www.newtis.info/tisv2/a/en/e...ol-dsc/iDP8oTz

Please let us know what you find,
George

[AnthBech]

Thank you for the very useful information George!

Ended up pulling the codes with a scanner and getting the same results as previously stated. In a fit of frustration I checked and cleaned the rear right sensor and cleaned it even though there was little to no dirt or visible signs of corrosion.

Reset the codes and took the car for a drive but the lights stayed ON.

Then I remembered having a similar issue with my old e46, so I stopped at a service station and tapped on the Hydraulic unit and ABS module with the back of a screwdriver. Sure enough, as I pulled away, the lights turned off!

Now that I’ve narrowed down to a faulty plug, hydraulic unit or abs module, I will begin the process of elimination and post my updates on this thread!

[gbalthrop]

Originally Posted by AnthBech

...Ended up pulling the codes with a scanner and getting the same results as previously stated. In a fit of frustration I checked and cleaned the rear right sensor and cleaned it even though there was little to no dirt or visible signs of corrosion. Reset the codes and took the car for a drive but the lights stayed ON.
Then I remembered having a similar issue with my old e46, so I stopped at a service station and tapped on the Hydraulic unit and ABS module with the back of a screwdriver. Sure enough, as I pulled away, the lights turned off!...

Did you tap in the Pump Motor, the Valve Block, or the Connector? It occurs to me that one of the codes you had earlier (which recurred I presume) was for a Faulty Connector. I presume that would be X18303 at the DSC Module, per this Installation Location and Connector View:
https://www.newtis.info/tisv2/a/en/e...x18303/RJPFfg1
https://www.newtis.info/tisv2/a/en/e...18303/CTLgAupK

If there were corrosion/water on the pins/sockets for the RR Wheel Speed Sensor: Pin 43, Yellow/Black wire, & Pin 42, Yellow/Brown wire; and also on the pins/sockets for the Left-Front Pad Wear Sensor: Pin 5, Yellow/Violet wire; & Pin 9, Black/Violet wire; THAT would account for the codes you are seeing AND the Live Data readout showing NO signal from RR Wheel Speed Sensor. Have you checked for Wheel Speed/Direction Readout?

Basic rule for Diagnostics: If mutiple faults occur at same time and go away at same time, look for common component/ wire/ Connector that is used by all, and X18303 seems to be the common link.

So I would begin by separating that connector, examining for any sign of water or corrosion, particularly on the outer two rows of pins/sockets, and examining any seal (for damage) that is supposed to keep water OUT. I would use a heat gun to dry pins & sockets fully, clean with Electronic Contact Cleaner, apply a light coat of Petroleum Jelly or Silicone Lube to any rubber seal, reassemble, clear codes, and see what happens.

Please let us know what you find,
George

[AnthBech]

Apologies for the extremely late update on this one. So we went through quite a few different procedures to isolate and identify the issue and it finally came down to 3 possible problems.

1- either the ABS module plug was faulty/dirty
2- the ABS module is faulty
3- the ABS hydraulic unit is faulty

To eliminate #1, we removed the plug and examined it, with no visible signs of damage or faults. We cleaned it then re-plugged it. This did not solve the issue.

Now that we know it isn’t actually the plug, we will be examining the module and if this has no positive outcome we will examine the actual pump. Being extreme DIYers, examining the actually circuitry of the module won’t be a problem for us to do at home (but if anyone else has these issues I would recommend one of the many module repair services online).

Will give an update once we’ve had the time to have a look at it!

[jwalker87]

I think I had those same 3 lights when my ABS module died a few years ago. I'm pretty sure it was just the carbon brushes in the motor, which is technically DIY-able but I decided to send my unit to https://modulemaster.com/rebuilds/ for a rebuild. No problems since.