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mcbonio

Wheel speed sensor issue?

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Next on the quickly shortening list of electrical faults my new e60 LCI has is a potentially faulty wheel speed sensor.

 

When cornering left slightly sharp, the traction control kicks in completely slowing the car down to about 5mph. I think can feel the car brake heavier on the front left side too, which makes me think the front left wheel speed sensor is faulty.

 

When DTC is enabled it corners left fine. I have no error codes present either... 

 

Whats your take on this guys?

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I've checked this over in DIS 57. All 4 sensors show the same speed and direction when travelling, and show no electrical or general fault.

 

The issue still plagues me, when ever I turn even lightly enthusiastically the car grinds to a halt....

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I had a similar issue on my old E39 in which the car would brake itself as though the car was skidding. It would lurch and dip in one corner even when on a flat, straight road.

 

Turned out to be the Yaw sensor/speed module under the carpet and under the passenger seat.

 

I did have an error though when checked with INPA and it pointed directly to the Yaw sensor.

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Ok, so had someone drive the whilst I monitored the DSC sensors on the laptop.

 

Everything seems ok I think, not sure what the "pressure_ACC_FA" and "pressure_ACC_RA" are though, they show !-27. Anyone know what these 2 values are?

 

3MGPbk8.png

vIA0TBN.png

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Was wondering if this is a steering angle issue, so I looked at it in INPA.

With the wheel at left lock is reads -358
With the wheel at right lock it reads -420

Is this normal that both left and right values are different?

Quote

 

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What is the steering angle reading with steering wheel straight ahead?

 

my steering wheel was off to the left from straight ahead, when driven hard and DSC intervened, the car would start drifting

 

had full alignment carried out, steering wheel straight ahead again and steering reads 0 degrees, no more drifting

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Hey Iain,

              Steering angle reads 0 when dead ahead and on the road it tracks perfectly....

 

I think it's a calibration issue, as the left and right lock values are very different. I had a look at calibrating the steering angle with DIS57, but there is no option to do so in the service functions which now makes me believe the SZL is not coded to the DSC correctly.

"

  1. Coding DSC
    On code the DSC, vehicle-specific data records are selected (e.g. size of the brakes). At the same time, the data for coding for the steering column switching centre is stored and transferred across the F-CAN to the SZL (not on the M5/M6). This means that if the SZL is replaced the DSC control unit also has to be coded. Without successful coding, no calibration of the steering-angle sensor is possible. 
    Even if there are faults in the DSC, coding is normally possible.
  2. Calibration of steering-angle sensor
    The zero point of the steering-angle sensor, the vehicle identification number and the serial number of the SZL are stored.

 

The SZL had been replaced with a used one at some point, probably after the car was in a minor accident during previous ownership. Drivers side wing was replaced with drivers airbag, looks like the SZL was blown apart when the airbag deployed. Perhaps who ever fixed the car didn't know how to code a used SZL.

 

I think I'll pull up the info in the SZL with Tool32 to see if the correct VIN is on there and the DSC to see if the serial from SZL is there. I miss my e30s, life was so much simpler... :)

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You should just be able to do E60>Functional jobs>AIF (or UIF) and that will bring up the part numbers and names of everything fitted, and also list the VIN numbers so you can spot if something is different.

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Ah yes I forgot about that End.!

 

Ok so, DSC module VIN says 0000000...  a couple of them also read  ŸŸŸŸŸŸŸ.   Whats best course of action, write correct vin to DSC with Tool32?

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The YYYY stuff is kinda normal, that turns up on modules that don't have the VIN written in them.

 

Recoding the DSC might put the VIN into it, otherwise tool32 would probably do it.

 

Look for something like FG_Schrieben in tool32, and when you click on that, it'll bring up a window saying what it is expecting, 7-stellig 17-stellig or 18-stellig which is 7 digit, 17 digit (complete VIN) or 18 digit, complete VIN with checksum.

 

I seem to recall a lot of DSC units have a 17 digit VIN in them, but they ignore the WBA at the start, so if you write the 17 digit, don't be alarmed if the first 3 digits are missing.

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The VO (or GM/SA/VN in this case) wouldn't be in the DSC, usually in the EWS, cluster, and LCM.

 

It should be able to be recoded by connecting with NCS expert, and then going straight to DSC/ABS coding and NCS will have sorted out the coding data automatically for factory defaults.

At that point, it'll probably copy over the VIN too.

 

 

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OK, the DSC60_PP lives under  "EHB3" in the choose module section of NCS.

 

I've tried coding it but I can't see which job I'm supposed to select for this in the choose jobs menu..?

sbIzLoK.jpg

 

 

 

in Tool32 under c_fg_schreiben I can't figure out how how the vin number wants to go in, tried it with the checksum too.

rR0uPKq.jpg

 

 

 

Also in tool32 under aif_schreiben it wants a series of text strings which I don't know how to do either.

CoYmVXa.jpg

 

About to give up and just code DTC on permanently... :(

 

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Dy a strange coincidence, I was just doing something similar on a 6 series, and that had the DSC60_PP which doesn't seem to work with INPA.

 

To recode the DSC, you'd go into that EHB3, select the SG_CODIEREN job and the Execute.

You'll probably get the lights flash on and off, and after a few seconds it should say "coding ended"

 

This is the info for the VIN write-

name      : C_FG_SCHREIBEN
  comment : Fahrgestellnummer schreiben
            Standard Codierjob
            KWP2000: $3B WriteDataByLocalIdentifier
            $90 Vehicle Identification Number
            Modus  : Default
result    : JOB_STATUS
  type    : string
  comment : OKAY, wenn fehlerfrei
            table JobResult STATUS_TEXT
argument  : FG_NR
  type    : string
  comment : Fahrgestellnummer (18-stellig)
result    : _TEL_AUFTRAG
  type    : data
  comment : Hex-Auftrag an SG
result    : _TEL_ANTWORT
  type    : data
  comment : Hex-Antwort von SG

 

It does say 18 stellig, so the full VIN with checksum. Maybe try ticking the Data box, but first off try the coding. To run a job, you want to click the 1*> button, which means 1 x run (eg run once)

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Was also experimenting today with conditions under which the ABS kicks in when turning, It seems to be more related to how fast you turn the wheel when cornering rather than how fast you are going when you corner. So a sharp turn of the wheel will kick it off rather than a slow turn at a faster speed. 

 

Also when it happens, the ABS will continue to pump away even when the car has completely stopped if you keep the wheel turned. The moment you straighten it up the ABS pumping stops, which makes me think still think the steering angle sensor is faulty. These LCI squibs have an optical disc that can be cleaned off, if that doesn't help I'll get another squib unit and try that.

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Ok, so progress.!   

 

I ran SG_CODIREN on EHB3 inside both CAS and LMA. Then in Tool32 checked the VIN number on DSC. It now shows my VIN.! Yay!

 

So a quick attempt to calibrate the steering angle, I reset the SZL ECU and initialized it in Tool32 the ran the steering wheel lock to lock a few times and took it for a drive, surprise surprise, It's totally transformed the car. It only kicks ABS in when you truly trash it around the corner at speed as you would expect, still the odd abs flash when going around a corner normally though but the car is now driveable with DSC on.

 

I also looked the the steering angle in INPA, it no longer reads 360 left, 420 right. But now changes from + and - values every quarter turn.  I'm going to clean the optical disc tonight and see if DIS57 will now give me the option to calibrate SZL.

 

What you think End?

Edited by mcbonio

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Well, it's getting better, but there seems to be something up with your steering angle sensor if it's going crazy like that.

Maybe the recalibration will sort it.

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