2002 E39 ASC BRAKE ABS lights on => Diagnostic Procedure & Parts Location

Originally Posted by boomshakalaka

about the fuel gauge. Without the abs unit in, mine has gone completely bonkers. I've seen the needle move a third of a tank in 5-10 seconds. I really don't know what input it is using

Yup. A lot of people reported an erratic fuel gauge. I was in disbelief until I saw mine, only when it was in the last quarter tank, bounce wildly.

When I asked why, I think the answers were that the speed sensor signals are used to calculate mileage (but that really didn't explain it to me).

Anyway, it's an enigma (to me) why a fuel gauge would need an ABS control module in place; but it apparently does. And, it's not the only thing!

I scoured the Internet to find the sum total of the anomalies, and came up with this tribal knowledge list:

While your ABS control module is out of the car, the following anomalies have been reported by others:
- Brake/DSC/ABS trifecta solid yellow lights (on the instrument cluster)
- Service Engine Soon (SES) solid yellow light lit (on the instrument cluster)
- No ABS (upon hard braking under low-traction conditions)
- No traction control (DSC or ASC on lateral action)
- No speedometer (use a portable GPS navigation unit if you're worried about that)
- No odometer (again, use a portable GPS unit if this bothers you)
- No tripmeter (use a portable GPS unit if it's a worry to you)
- No cruise control
- OBDII diagnostic trouble code DTC P0500, i.e., bad speed sensor (clear by driving or with an OBDII scanner)
- No possibility of passing (California at least) smog inspections (until you replace the ABS control module & clear the DTC)
- No speed-sensitive automatic door locks (if enabled at the stealer)
- No GPS (if you have navigation)
- No mileage calculations on the instrument cluster
- No fuel consumption calculations on the instrument cluster
- No range indications on the instrument cluster
- No speed-sensitive radio (if equipped)
- No speed-sensitive wipers (if equipped)
- Erratic fuel gauge (especially when near empty, so keep the tank at greater than 3/4 at all times)
- Erratic transmission shifting (if automatic; if it bothers you, switch to manual shifting)

Well, I just took 10 minutes to disconnect the battery, take off the airbox screw so I could push it aside to give room to tighten the torx bolts on the abs, and put everything back in place. Only drove about a mile, but DSC and ABS are working perfectly so far! Such a relief.. I dealt with this problem for almost the entire time I've had the car, just figuring I could live with some silly lights on the dash and a lack of abs/dsc if fixing it meant spending over $1,000. Just wish I found out that it only cost a two hundred dollars and is a DIY removal/reinstall..

Originally Posted by boomshakalaka

I dealt with this problem for almost the entire time I've had the car

Don't feel badly. I didn't even know if I had ASC or DSC when I started this quest!

In fact, it took me a year from start to finish this job ... which turns out to be, in reality, a simple and common and well characterized problem. But I didn't know that when I started this thread or I wouldn't have started it in the first place.

The tribal knowledge of the guys here is fantastic!

BTW, as another similar rags-to-riches example, I just today put my headlights back in my car, after having headlight adjuster issues in May of 2009 (so it took me a year and a half this time!).

When I started that thread, I didn't even know where the headlight adjusters were, nor how to remove the headlights from the E39. But now I know as much as anyone about what they're made of, how they break, how to remove the headlights, how to open them up, what the purpose of each and every part is inside the headlight, how to break them (yup, I broke a few things inside), how to replace them, what brands are best, what suppliers are there to assist us, etc.

The point is that the combined tribal knowledge of this group is so fantastic, that, with time, they can even bring ignorant fools like you and me up to the level that we can know more than some of the so-called mechanics out there who work on cars day in and day out.

That's powerful!

Point is, some of us may start real styupid (like you and me) with this ABS/BRAKE/DSC problem; but, with the help of the wonderful guys here, we learn, over time, what they already know!

Now, the hope is that we can give back to the team. That is your task (and mine) ... we need to ask, listen, and learn - and then it's our payback duty to increase the tribal knowledge value of this wonderful team!

Good luck,
BB

link to headlight adjuster thread?

Originally Posted by boomshakalaka

link to headlight adjuster thread?

It was there in the previous post. Look where I said "after having headlight adjuster issues in May of 2009".

Anyway, if you need headlight adjuster threads, the bestlinks sticky has the best of 'em already listed:
- HEADLIGHT ADJUSTERS CRUMBLE: brittle plastic headlight adjusters that simply crumble over time causing the lights to point downward (0) (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16) (17) & a comprehensive list of all your available options, by price (1)

You are a god amongst men.

Originally Posted by amerritt74

Did anyone ever find a pin out for the module with the vertical connector? (1998 528i)?

The question came up again, rather elegantly, in this 1997 528i thread today:
- ABS, ASC, BRAKE lights Bosch 5.0 PLease HELP!!!!

Did we ever determine conclusively what the test sequence is for the older Bosch 5.0 units?

It would be nice to get a report back from these users:
- e39vinay, Bosch 5.0, 525D (his post is here where he lists the pinout of the X1171 harness connector) <---- this should help a lot
- tspeed, 1998 528 (his post is here)
- softtouch, 528i (his post is here)
- amerritt74, 1998 528i (his post is here)
- eafrost, 1997 528i, (his post is here)

Here's the X1171 connector pinout from e39vinay:
Pin assignments at connector X1171

Pin Type Description / Signal type Connection /
Measuring notes
1 E Voltage supply, terminal 15 Terminal 30 voltage supply Fuse F17 DDE Fuse F31 DME
2 A Valve control Hydraulic unit, Left front inlet valve
Relay control
3 A Relay control Valve and motor relay
4 Not used
5 Not used
6 A Valve control Hydraulic unit, Right rear inlet valve
Relay control
7 A Relay control Motor relay
8 Not used
9 A Engine speed signal Left front wheel speed splice
10 A Engine speed sensor voltage supply Left front speed sensor
11 E Engine speed sensor signal Right rear speed sensor
12 A Engine speed sensor voltage supply Left rear speed sensor
13 E Engine speed sensor signal Left rear speed sensor
14 A Engine speed sensor voltage supply Right front speed sensor
15 E Engine speed sensor signal Right front speed sensor
16 Not used
17 Not used
18 A Increase idle speed signal Engine control module (DME)
19 E B+ power/feedback Engine control module relay, terminal 87
20 Not used
21 Not used
22 Not used
23 A Voltage control Auxiliary throttle position motor (ADS) DME
24 E Generator signal Generator control splice DME
25 A Valve control Hydraulic unit, Left rear outlet valve
26 A Valve control Hydraulic unit, Intake valve
27 A Valve control Hydraulic unit, Right front outlet valve
28 M Ground Ground point
29 M Ground Ground point
30 A ABS malfunction indicator lamp Instrument cluster
31 A ASC malfunction indicator lamp Instrument cluster
32 Not used
33 A Valve control Hydraulic unit, Left front outlet valve
34 A Valve control Hydraulic unit, Right rear outlet valve
35 E Engine speed sensor signal Left front speed sensor
36 A RH rear engine speed signal Transmission control module (AGS)
37 A Relay control Valve relay
38 A Engine speed sensor voltage supply Right rear speed sensor
39 M Component ground ASC throttle position sensor DME
40 A LH rear engine speed signal Left rear wheel speed splice
41 Not used
42 A RH front engine speed sensor Right front wheel speed splice
43 A Throttle position sensor voltage supply ASC throttle position sensor DME
44 E ASC passive sensor signal ASC/DSC switch
45 Not used
46 E/A Data link TXD Data link connector
47 Not used
48 E Brake signal Brake light switch
49 A Valve control Hydraulic unit, Changeover valve
50 Not used
51 E Throttle actuator terminal 30 voltage supply Fuse F8 DME
52 A Valve control Hydraulic unit, Left rear inlet valve
53 A Ground control Auxiliary throttle position motor (ADS) DME
54 A Valve control Hydraulic unit, Right front inlet valve
55 M Ground Ground point
56 Not used
57 Not used
58 Not used
59 Not used
60 Not used
61 E/A CAN-bus high Engine control module (DME)
62 Not used
63 E/A CAN-bus low Engine control module (DME)
64 Not used
65 Not used
66 Not used
67 E Throttle position sensor slider voltage ASC throttle position sensor DME
68 Not used
69 Not used
70 Not used
71 Not used
72 Not used
73 Not used
74 Not used
75 Not used
76 E Park brake signal Park brake switch
77 A Ignition timing signal Engine control module (DME)
78 Not used
79 Not used
80 Not used
81 A Ignition fade-out signal Engine control module (DME) DME
82 Not used
83 A Transmission influencing signal Transmission control module (AGS) DME
84 A Power Hydraulic unit DDE Hydraulic unit
85 Not used
86 Not used
87 Not used
88 E DKI signal Engine control module (DME) DME
Note: At the cluster, the speed sensor wire is the brown/red wire (white connector 26 pins) found at pin 17.

Couldn't you just use WDS to find the connector you are looking for?

http://spaghetticoder.org/bmw/wds/

or

http://www.bmw-planet.com/diagrams/release/en/

It has certainly helped me once, when my P-bus cable from the door was broken.

The information below, posted today, by Saher may help others with the older-style harness connector ...

My car is a 1997 E39, so the ABS connector looks significantly different, however I think I was able to test sensors. At the bottom of my connector to the right there were 4 pin holes and to the left there were 2. I tested the resistance between each of the 2 left pinholes and each of the left 4 pinholes and noted that I was getting a consistent reading for each of them (3-4) that was not 0 or infinity, so I assumed that the resistors are fine.

Next I took off each of the wheel speed sensors and cleaned them using "Goo Gone". AND IT WORKED!!!!!!!
I'm actually writing this from work, which is 30 miles away, and until now the ABS and Traction lights are off and the car shifts normally again.

Bluebee,

You said your brake pressure sensor was not working, I am wondering how did you test out this? Did you change it before send the DSC part in for a rebuild?

Originally Posted by truelies

Bluebee,

You said your brake pressure sensor was not working, I am wondering how did you test out this? Did you change it before send the DSC part in for a rebuild?

It's exasperating ...

This same question has come up multiple times in this thread. Bill (540iman) has explained what is going on numerous times also.

The "brake pressure sensor" diagnosis code is a red herring. It's not real. Almost all the codes are not real (Bill explains why many times so I'm simplifying w/o going into the details).

Yes, at one point, the brake pressure sensor warning had me fooled. And yes, we did come up with the test from the BMW TIS. The test is very simple and needs only a volt ohmmeter to measure 5 volts but it requires "flying leads" so, unless you REALLY think your brake pressure sensor is bad, I wouldn't bother with the test (I didn't).

The point is that almost all the diagnostic codes are DEAD WRONG when it comes to this problem.

I understand we're all looking to replace/rebuild something other than the (expensive) ABS control module; but it turns out that it's very difficult to believe ANY diagnostic code when it comes to this type of failure.

Time and time and time again this has been borne out. Bill can give you the details why (actually he did, already, many times, in this thread and in others).

If you think it's the "brake pressure sensor", then look at the BMW TIS posted in one of the prior links which shows how to test it. Also look at some of the pictures I posted which show how to make the 'flying leads'.

Good luck. If you make the flying leads, please post a picture so we can get a better idea as I don't think ANYONE has ever built one and posted a picture of it.

Originally Posted by bluebee

It's exasperating ...

This same question has come up multiple times in this thread. Bill (540iman) has explained what is going on numerous times also.

The "brake pressure sensor" diagnosis code is a red herring. It's not real. Almost all the codes are not real (Bill explains why many times so I'm simplifying w/o going into the details).

Yes, at one point, the brake pressure sensor warning had me fooled. And yes, we did come up with the test from the BMW TIS. The test is very simple and needs only a volt ohmmeter to measure 5 volts but it requires "flying leads" so, unless you REALLY think your brake pressure sensor is bad, I wouldn't bother with the test (I didn't).

The point is that almost all the diagnostic codes are DEAD WRONG when it comes to this problem.

I understand we're all looking to replace/rebuild something other than the (expensive) ABS control module; but it turns out that it's very difficult to believe ANY diagnostic code when it comes to this type of failure.

Time and time and time again this has been borne out. Bill can give you the details why (actually he did, already, many times, in this thread and in others).

If you think it's the "brake pressure sensor", then look at the BMW TIS posted in one of the prior links which shows how to test it. Also look at some of the pictures I posted which show how to make the 'flying leads'.

Good luck. If you make the flying leads, please post a picture so we can get a better idea as I don't think ANYONE has ever built one and posted a picture of it.

So actually you pressure sensor was good. Is that correct? Since you said "it's bad" in the the summary post of this thread, I am wondering if I need to test it. Thanks!

Originally Posted by truelies

So actually you pressure sensor was good. Is that correct? Since you said "it's bad" in the the summary post of this thread, I am wondering if I need to test it. Thanks!

Yes. Around post #48, I said it was bad because I "thought" it was bad because a diagnostic tool reported that as the symptoms.

But it was good. I never tested it. Bill, who really was the genius that got the testing suite all figured out, convinced me that all the diagnostic tools were reporting symptoms but that none of the diagnostic tools could report the problem (because of the way they're hooked up).

At another point, later in the thread IIRC, I got a DIFFERENT errant reading (of a bad wheel speed sensor) from the diagnostic tools. This time I knew it was bogus because I had already tested all four wheel speed sensors and knew they were good.

In fact, even after I had my ABS control module rebuilt by ATE, I still failed smog inspection a couple days later because there was still an errant P0500 wheel speed sensor malfunction listed as a pending DTC (which needed to be cleared).

But, all the diagnostic tools in the world will fail you in this particular situation. All this is said in subsequent posts of this thread so I'm repeating myself.

This is a (quick) summary of what the diagnostic tree "we" (tribally) recommend:
If you have the amber trifecta (BRAKE + DSC + ABS)...

• A. Test (with a DMM in the engine bay) the four wheel speed sensors ...
• B. If one wheel speed sensor is bad, test that one at the wheel (if more than one show up as bad, your technique is likely suspect) ... and if that one still tests bad, clean it ... and if it still tests bad, replace it.
• C. Otherwise, rebuild the ABS control module (generally one steel power wire lifts off its gold bondpad but sometimes the gold signal wires flop over onto each other).

BTW, this "amber ABS BRAKE DSC trifecta diagnostic tree" is sooooo simple, ironically, it's the reason it took me a year to believe in it (even though it was told to me in the beginning). I just couldn't believe it was that simple - I kept looking for a diagnostic aid to locate 'the culprit'.

Thank you so much for this thread.

My ABS, DSC and BRAKE lights a lit up in yellow about a week ago. Nothing seems to have changed, i just have the lights on. At first they would not come up when I first started the car but now I think they come on as soon as I start the car.

I still need to read through this whole thread so I don't ask any questions that have already probably been answered multiple times. I just wanted to tag this thread and say thanks.

Originally Posted by Cyrax71

Thank you so much for this thread.

You're welcome.

Today, yet another person asked for a pinout for a 1997 BMW 528i e39:
- Intro to BMW Ownership - HELP!

This has happened before:
- Need ABS Module Pin Out for 1997 528i

And, in detail, we've answered the question in this thread above (scattered about in various places, including post #224, post #264 post #307, etc.).

See also:
abs_teves4eng.pdf (53.3 KB, 22 views)

But the one thing people with the 1997 E39 need is the picture below A N N O T A T E D with the pinouts, at the very least, for the 8 wires going to the four wheel speed sensors.

May I ask those with the 1997, who have a need to test their wheel speed sensors, please annotate this picture (not for me, but for others to benefit) below with the pinouts?

For the record, today Freyg kindly provided values for the four wheel speed sensors.

Here are his values (in text), with mine below that (in chart form).

It would be useful if the next person who checks their wheel speed sensors also reports the values as we can get an idea of the normal range from this information.

Left Rear (FB) - 1.087 Volts 11.25 Mohm
Left Rear (RB) - 0.666 Volts 26.74 Mohm

Right Rear (FB) - 1.090 Volts 11.47 Mohm
Right Rear (RB) - 0.674 Volts 27.28 Mohm

Left Front (FB) - 1.093 Volts 11.63 Mohm
Left Front (RB) - 0.676 Volts 27.82 Mohm

Right Front (FB) - 1.096 Volts 11.72 Mohm
Right Front (RB) - 0.675 Volts 27.90 Mohm

Today I tried to test the four speed sensors, I did the Diode Test, but all the values are '1', don't know what's wrong. Do we need to start the car for this test? I didn't insert the key into the car.

Originally Posted by truelies

Today I tried to test the four speed sensors, I did the Diode Test, but all the values are '1', don't know what's wrong. Do we need to start the car for this test? I didn't insert the key into the car.

I'm interested in this topic because I'm about to tackle the same problem. From my reading of the algorithm, you need to reverse the polarity of the test leads when you check each wheel sensor. This means you should get two readings for each wheel. Did you do this? If so, and all eight of the readings are the same, the problem is probably in the way you attached the leads. Regardless of whether you use the diode test or resistance test, getting the same readings for both polarities on all four wheel sensors is unlikely, because that would mean that all four failed at one time. If you just get one sensor with two identical readings, then that sensor has likely failed.

I read elsewhere, but now I can't find the link, that a failure upstream can have a "cascade effect" and cause the module to fail. If this is true, just rebuilding or replacing the module won't be a permanent fix. Once a certain number of errors accumulate in the memory, it could fail again. This makes me think that we should have pin outs for all the sockets in the module connector so that we can test the other sensors that feed into it. Does this sound reasonable?

Like many people I couldn't get result with diode mode of DMM, all 8 positions got '1'(I think this means 0L)
So I decided just remove the DSC and send in to rebuild.

After remove it, I began to fix my rear bulb problem. I turned the lights on and off several times. Suddenly the car lost power, seems like the battery is very weak. How to deal with this? now my car can't move. If I remove the key, will the car charge the battery itself?



[QUOTE=530i-bie;5607898]I thought I would send a reply feedback/update to my problem...
Since I could not find anything wrong with any of the inputs to the ABS module, and no one had any other hopeful suggestions (thanks to all who offered input on this thread !!),
I sent my module off to BBA Reman. I won an EBAY auction for their service for $168.00, paid the 2nd day shipping option. Had excellent email communications with them. They

Mine is different after removed the ABS module

DSC/ABS trifecta solid yellow lights, no Brake light
SES light not ON.

Originally Posted by bluebee

Yup. A lot of people reported an erratic fuel gauge. I was in disbelief until I saw mine, only when it was in the last quarter tank, bounce wildly.

When I asked why, I think the answers were that the speed sensor signals are used to calculate mileage (but that really didn't explain it to me).

Anyway, it's an enigma (to me) why a fuel gauge would need an ABS control module in place; but it apparently does. And, it's not the only thing!

I scoured the Internet to find the sum total of the anomalies, and came up with this tribal knowledge list:

While your ABS control module is out of the car, the following anomalies have been reported by others:
- Brake/DSC/ABS trifecta solid yellow lights (on the instrument cluster)
- Service Engine Soon (SES) solid yellow light lit (on the instrument cluster)
- No ABS (upon hard braking under low-traction conditions)
- No traction control (DSC or ASC on lateral action)
- No speedometer (use a portable GPS navigation unit if you're worried about that)
- No odometer (again, use a portable GPS unit if this bothers you)
- No tripmeter (use a portable GPS unit if it's a worry to you)
- No cruise control
- OBDII diagnostic trouble code DTC P0500, i.e., bad speed sensor (clear by driving or with an OBDII scanner)
- No possibility of passing (California at least) smog inspections (until you replace the ABS control module & clear the DTC)
- No speed-sensitive automatic door locks (if enabled at the stealer)
- No GPS (if you have navigation)
- No mileage calculations on the instrument cluster
- No fuel consumption calculations on the instrument cluster
- No range indications on the instrument cluster
- No speed-sensitive radio (if equipped)
- No speed-sensitive wipers (if equipped)
- Erratic fuel gauge (especially when near empty, so keep the tank at greater than 3/4 at all times)
- Erratic transmission shifting (if automatic; if it bothers you, switch to manual shifting)

Originally Posted by truelies

Do we need to start the car for this test?

I took a look at the procedures; they CLEARLY state what to do with the ignition!

Originally Posted by bobdmac

a failure upstream can have a "cascade effect" and cause the module to fail. If this is true

I don't know "if" it's true (so I won't say either way); but I must point out that almost all (all?) the module failures we've autopsied, they have been either the steel large wire lifting off its gold bondpad or the flimsy gold wires touching one another. Those "repairs" were successful - and I doubt either type would be "caused" by a bad wheel speed sensor.

So, personally, (without any other datapoints), I doubt a "bad" wheel speed sensor is what is causing the Bosch 5.7 ABS control modules to fail.

Originally Posted by bobdmac

we should have pin outs for all the sockets in the module connector so that we can test the other sensors that feed into it. Does this sound reasonable?

I think we already listed the pinouts of every single wires in the ABS control module harness connector (both for the 1997 and for the later E39s) in this thread; so what we need, to take this the next step, is to figure out what the "values" should be.

We could, if we wanted to, figure that out with not too much effort because of the wonderful DSC pdf from Max_VQ that was posted in post #61.

This PDF shows exactly how to test ALL the DSC sensors (there are about a score of them) if I remember correctly.

*******> ********>*******>********>

DSC part 1.pdf (988.0 KB, 1538 views)

DSC part 2.pdf (771.1 KB, 1651 views)

Originally Posted by bluebee

I don't know "if" it's true (so I won't say either way); but I must point out that almost all (all?) the module failures we've autopsied, they have been either the steel large wire lifting off its gold bondpad or the flimsy gold wires touching one another. Those "repairs" were successful - and I doubt either type would be "caused" by a bad wheel speed sensor.

So, personally, (without any other datapoints), I doubt a "bad" wheel speed sensor is what is causing the Bosch 5.7 ABS control modules to fail.

I was thinking of something like the hydraulic pressure sensor (don't remember exactly what it was), and I believe there were reports of of the problem recurring after the ABS module was repaired or replaced.

Originally Posted by bluebee

I think we already listed the pinouts of every single wires in the ABS control module harness connector (both for the 1997 and for the later E39s) in this thread; so what we need, to take this the next step, is to figure out what the "values" should be.

Thanks, Bluebee. I missed that somehow.

Originally Posted by bluebee

We could, if we wanted to, figure that out with not too much effort because of the wonderful DSC pdf from Max_VQ that was posted in post #61.

This PDF shows exactly how to test ALL the DSC sensors (there are about a score of them) if I remember correctly.

The ABS module is on my menu of things to fix. If no one's posted the info by the time I get to it, I'll see what I can find.


*******> ********>*******>********>

DSC part 1.pdf (988.0 KB, 1538 views)

DSC part 2.pdf (771.1 KB, 1651 views)

[/QUOTE]

Originally Posted by bobdmac

Thanks, Bluebee. I missed that somehow.

I know it's here because I laboriously typed it up by hand from my Bentleys!

I learned my lesson. Half way through I wanted to stop but figured I had already typed half of it ... so I continued, page after page after page.

Next time I'd just include a picture of the Bentleys - but anyway- I'm absolutely positive we have the harness connector pinout typed up here ('cuz I typed it up!).

Originally Posted by bobdmac

The ABS module is on my menu of things to fix.

You can try to fix it yourself.

In the VERY best of E39 Links is this reference:
- ABS control module autopsy (specific instructions necessary for a competent repair)

The good news is that, if you screw up, the rebuilders will "still" take your ABS control module (they say they get opened ones all the time).

So you don't have anything to lose by opening it up and taking a look.

I have a question:

Hydraulic Pressure Sensor and the brake Pressure Sensor are same thing, is that correct?

Hi,

New to the forum and have the same problem as most on here, 3 yellow lights on dash and speedo comes and goes from time to time. When I start up in the morning all is well until the car heats up then the lights come on and the speedo comes and goes as does the cruise. I have a friend who works for BMW who hooked up the car to the diagnostic machine which said it was a brake pressure sensor fault. Ive read this post and notice as said many times that this is not necessarily the fault and could still be the module thats at fault, I was leaning toward the module due to the fact the speedo is coming and going intermitantly as is the cruise however I tried testing the pressure sensor by back probing and noticed I was getting a constant 4.8V from both live wires even when the brake pedal was being pushed with the engine running. from what ive read the voltage should change depending on the pressure applied to the pedal. Does this sound like the pressure sensor or could this still be a module issue?

Thanks