[Scottycs]

SOLVED: Problem partially resolved, post #35

Hi All,

After leaving the e90 platform (2009 335i) I picked up a 2009 328i for a daily driver.

I have the common non stop wipers, ABS, DSC, Brake Lights, no MPH. I have been unable to communicate DSC, the module does not show up in identification or scans. I thought the DSC/ABS module was bad, so I replaced it with a used unit. No communication..... Tried another..... No communication. My next thought is the SZL, could a bad SZL destroy the communication with the DSC? Any help greatly appreciated.

Error codes attached.

[Scottycs]

bueller?

[dpaul]

Originally Posted by Scottycs

bueller?

Although connected via F-CAN, I don't think a bad SZL could specifically bring down the DSC without affecting other modules on that bus. That's a guess.

AFAIK, ALL your errors indicate communication failures with DSC via PT-CAN bus. The DSC is the gateway for SZL communication to the JBE via PT-CAN and the wipers come on because JBE interprets this lack of communication as SZL failure.

Consistent with the errors, DSC is the only module that INPA doesn't find. That could be explained by a DSC failure, a bus wiring failure or a power supply failure. You replaced the module twice without restoring communication which likely eliminates DSC module failure.

Honestly, the first thing I'd check would be the fuses that supply power to the DSC. If you cannot determine which fuses are relevant, provide the last 7 characters of your VIN and I'll look it up for your

[Scottycs]

Thanks for the reply!

Not to throw a wrench at you, but I have some other issues that I did not mention in my original post that lead me to believe the SZL is causing the issue.

-MPH dead
-Turn signal will not reset
-steering wheel buttons dead (but they do light up)

Clearly there is NO communication however I try. Could a failure of one unit bring down the whole network?

I have checked the fuses numerous times and they appear good. I do not know if the previous owner removed a fuse which could be causing this? I also checked the power wires at both the SZL and DSC connectors, both have power. That as far as I go with a multimeter.

Last 7 of my Vin are NM4759.

Thanks again!

Originally Posted by dpaul

Although connected via F-CAN, I don't think a bad SZL could specifically bring down the DSC without affecting other modules on that bus. That's a guess.

AFAIK, ALL your errors indicate communication failures with DSC via PT-CAN bus. The DSC is the gateway for SZL communication to the JBE via PT-CAN and the wipers come on because JBE interprets this lack of communication as SZL failure.

Consistent with the errors, DSC is the only module that INPA doesn't find. That could be explained by a DSC failure, a bus wiring failure or a power supply failure. You replaced the module twice without restoring communication which likely eliminates DSC module failure.

Honestly, the first thing I'd check would be the fuses that supply power to the DSC. If you cannot determine which fuses are relevant, provide the last 7 characters of your VIN and I'll look it up for your

[dpaul]

Originally Posted by Scottycs

Thanks for the reply!

Not to throw a wrench at you, but I have some other issues that I did not mention in my original post that lead me to believe the SZL is causing the issue.

-MPH dead
-Turn signal will not reset
-steering wheel buttons dead (but they do light up)

Clearly there is NO communication however I try. Could a failure of one unit bring down the whole network?

I have checked the fuses numerous times and they appear good. I do not know if the previous owner removed a fuse which could be causing this? I also checked the power wires at both the SZL and DSC connectors, both have power. That as far as I go with a multimeter.

Last 7 of my Vin are NM4759.

Thanks again!

Some module failures could affect the operation of other modules attached to the same bus. But For me it's hard to put that together with your constellation of issues and it would not explain why only the DSC is not reachable and is undetected by INPA. MPH is dead because KOMBI can't get any information about wheel movement from the DSC. Not sure about the others but I suspect similar origins - no communication with DSC.

Did you look at all three fuses F82 F90 and F26?

12+ at the ABS module would be pins 32, 1 and 17 and grounds (worth checking) are 16 and 37 (assuming you are RWD)

[TyroneShoelaces]

OP FWIW my DSC is still not right while sort out my awd to rwd swap and I have all the same symptoms of turn signals not canceling, dead wheel controls, all the lights on etc. Mine is a communication issue too. I can kinda talk to it but it's not happy and tells me that there is an issue in the connector.

[Scottycs]

Yes on the fuses. They all were good.

I did not check the grounds or the other pins for power, I can check those tonight. I just find it odd that the unit is completely unresponsive (Original, rebuilt unit and now used unit).

But based on turn signals not canceling, I can assume SZL is dead? However certain functions do work from the control stalks.

[dpaul]

Originally Posted by Scottycs

Yes on the fuses. They all were good.

I did not check the grounds or the other pins for power, I can check those tonight. I just find it odd that the unit is completely unresponsive (Original, rebuilt unit and now used unit).

But based on turn signals not canceling, I can assume SZL is dead? However certain functions do work from the control stalks.

Whether the SZL has a problem or not, you still cannot connect to the DSC. Your thesis is that a dead SZL could somehow totally disable the DSC seems very unlikely to me. The connection between SZL and DSC is via the F-CAN bus and I doubt very much that shorting, opening or putting a stream of nonsense on the F-CAN bus would cause the DSC to be unreachable because INPA's connection to DSC is via PT-CAN through the JBE gateway. A module disappearing from INPA is usually the result of a completely bricking or a loss of power.

So, check the grounds first, easy enough to do.

Just to be clear, you are sure that the DSC modules you tried were from RWD vehicles, not Xdrive?

[Scottycs]

Good point! What you are saying completely makes sense, so it would appear there is no communication on the F-Can at all. But even if that is the case, I don't understand why the PT-CAN is not detecting the unit. I will check all the grounds tomorrow morning. The JBE is connecting and the faults on it are C918, A6CA, A6C9 which I assume 2 are from removing the wiper relay. Any clue on C918? I did remove some of the fuses while key was in the ignition to check them.

The DSC modules were RWD and the exact same part numbers.

Originally Posted by dpaul

Whether the SZL has a problem or not, you still cannot connect to the DSC. Your thesis is that a dead SZL could somehow totally disable the DSC seems very unlikely to me. The connection between SZL and DSC is via the F-CAN bus and I doubt very much that shorting, opening or putting a stream of nonsense on the F-CAN bus would cause the DSC to be unreachable because INPA's connection to DSC is via PT-CAN through the JBE gateway. A module disappearing from INPA is usually the result of a completely bricking or a loss of power.

So, check the grounds first, easy enough to do.

Just to be clear, you are sure that the DSC modules you tried were from RWD vehicles, not Xdrive?

[dpaul]

C918 is failure of jbe to receive msg from szl/ihka/lws. Prob about wipers

[dpaul]

https://bmwfault.codes/

[Scottycs]

Thank you! I didn't get a chance to check the grounds, but I did drive the car briefly. The gas gauge was bouncing empty to 1/4-1/2 randomly which would trigger low fuel ding and warning. Not sure if that helps in any way.

Originally Posted by dpaul

https://bmwfault.codes/

[Scottycs]

All power and grounds good! All fuses good as well.

Could the JBE failing?

Originally Posted by dpaul

Some module failures could affect the operation of other modules attached to the same bus. But For me it's hard to put that together with your constellation of issues and it would not explain why only the DSC is not reachable and is undetected by INPA. MPH is dead because KOMBI can't get any information about wheel movement from the DSC. Not sure about the others but I suspect similar origins - no communication with DSC.

Did you look at all three fuses F82 F90 and F26?

12+ at the ABS module would be pins 32, 1 and 17 and grounds (worth checking) are 16 and 37 (assuming you are RWD)

[gbalthrop]

Please see my Reply to your post in the other thread: "DSC problems".
I provided specific INPA steps to get more information. ALSO, please electrically test fuse F26 (F82 & F90 as well). When a Module (here 29 DSC) does NOT appear on "Functional Jobs > F2 Identification", or "Functional Jobs > F4 Error Memory, ALL Modules", EITHER:
1) No power or ground to that Module (F26?), or
2) Bus Failure (here PT-CAN bus) between DSC Module and JBE Gateway.

The Fault Details and Definitions from DME, EGS & KOMBI faults, as read by INPA and translated using Google Translate will likely offer clues that narrow the search and testing. INPA can also display Live Data, and do Activations, but the first issue is WHY no communication with DSC.

Please also provide your Last-7 Characters of VIN so we're sure we have correct wiring info from ISTA. I'll provide location and Connector View of pertinent Connector, Pins & Sockets to test at the DME connector next to Brake Fluid Reservoir under the hood. After F26, corrosion/moisture in that connector is next suspect. Then Connector at JBE.

Do you know WHEN the Blower Wiring Harness Recall was performed?
George

[Scottycs]

I will get screenshots (not photos) today to share.

There is power at the module. I have changed the fuse and tested power AND grounds on the harness.

2) I think there is a BUS failure. DSC and SZL are both not working.

No clue on the recall unfortunately, it was done prior to picking up the car.

Last 7 of my Vin are NM4759.

Thank you for your help, it is appreciated!

Originally Posted by gbalthrop

Please see my Reply to your post in the other thread: "DSC problems".
I provided specific INPA steps to get more information. ALSO, please electrically test fuse F26 (F82 & F90 as well). When a Module (here 29 DSC) does NOT appear on "Functional Jobs > F2 Identification", or "Functional Jobs > F4 Error Memory, ALL Modules", EITHER:
1) No power or ground to that Module (F26?), or
2) Bus Failure (here PT-CAN bus) between DSC Module and JBE Gateway.

The Fault Details and Definitions from DME, EGS & KOMBI faults, as read by INPA and translated using Google Translate will likely offer clues that narrow the search and testing. INPA can also display Live Data, and do Activations, but the first issue is WHY no communication with DSC.

Please also provide your Last-7 Characters of VIN so we're sure we have correct wiring info from ISTA. I'll provide location and Connector View of pertinent Connector, Pins & Sockets to test at the DME connector next to Brake Fluid Reservoir under the hood. After F26, corrosion/moisture in that connector is next suspect. Then Connector at JBE.

Do you know WHEN the Blower Wiring Harness Recall was performed?
George

[dpaul]

Originally Posted by Scottycs

I will get screenshots (not photos) today to share.

There is power at the module. I have changed the fuse and tested power AND grounds on the harness.

2) I think there is a BUS failure. DSC and SZL are both not working.

No clue on the recall unfortunately, it was done prior to picking up the car.

Last 7 of my Vin are NM4759.

Thank you for your help, it is appreciated!

1) There is obviously no general PT-CAN bus failure - DME, EGS and EKP are accessible and the vehicle runs.

2) Once again, DSC is the gateway for SZL to the PT-CAN bus so it is not surprising that if the DSC disappears, so does SZL function. SZL is connected to the DSC via F-CAN bus but F-CAN has no direct connection to K-CAN so: SZL->F-CAN->DSC->PT-CAN->JBE->K-CAN and D-CAN->OBDII connector->INPA

3) One explanation would be an open PT-CAN line to the DSC. Simple enough to check for continuity between DSC and DME connectors (DME connector X60001, pin 1 = PT-CAN L, pin 14 = PT-CAN H). DSC connector you already know since you've tested power and grounds.

[gbalthrop]

Originally Posted by Scottycs

... Last 7 of my Vin are NM4759...

When I count on my fingers, that's ONE hand, PLUS ONE finger.
Need SEVEN (7).

I'll go ahead and post ISTA ScreenPrints for 2009 328i, showing PT-CAN bus connectors related to DSC. As stated earlier, if DSC Power Supply & Ground OK, then connector at DSC, pins & sockets related to PT-CAN are next suspect.
George

[gbalthrop]

As stated earlier, I had NOT read through all posts in this thread before entering, so my apologies for repeating some of the things
others, such as "dpaul" had said. Dpaul also identifies the "bus route", and if you look at the FIRST attachment, showing the X18303
Connector and location of the PT-CAN & F-CAN Bus wires at that connector, my SWAG would be an issue with X18303 Pins/Sockets.

Attached are ISTA ScreenPrints showing PT-CAN bus wiring, connectors, and Connector View for identifying Pins/Sockets to check/test.
The SZL signals go to the DSC via the F-CAN bus (see X18303 Connector View).

To Clarify/Summarize: At X18303, shown in 1st screenprint, Pins#15 & #30 are PT-CAN; Pins #11 & #26 are F-CAN; Pins #17, #1 & #32
are B+; and Pins #16 & #47 are GND. High likelihood issues are caused by one or more of those pins/sockets.
George

[Scottycs]

Left the last 0 off the vin when copying it

Attached are the detail screenshots and I will be testing the continuity between the DSC and DME this afternoon.

[Scottycs]

EGS module, read through E83 profile

[gbalthrop]

Originally Posted by Scottycs

Left the last 0 off the vin when copying it
Attached are the detail screenshots and I will be testing the continuity between the DSC and DME this afternoon.

I would suggest BEFORE opening up the E-box where DME is located, just remove the cover on the OTHER/Left side and disconnect the DSC Connector, X18303, and inspect pins & socket there.

Since this vehicle is "New-to-YOU", be aware that there is a distinct possibility that "Attilla the Automotive Electrocutor" worked on that car at some time in the past. Your DME Codes show:

Seven (7) "Botschaft" = Message faults, 5 of which relate to the DSC Module
Two Unknown Error Location faults, related to EWS4 & ECTS
Fuel Pump & IHKA "Messages" due to issue with bus communication.

While there are a number of rabbit-holes that may appear attractive, I would suggest focusing on WHY no communication with DSC, and WHY it does NOT appear on Fault Memory List (29 DSC). Since the BULK of the faults in other modules relate to "NO Message from DSC", that appears to be the logical place to start.

Does the engine start and run in relatively-normal fashion? If so, I presume the DME Fault related to DME Communication with EWS4 (12108 Decimal = 2F4C Hexadecimal = U0167), "NOT Currently Present", is NOT a factor. If there ARE currently issues related either to starter cranking or engine start, save & post any CAS module faults (you earlier showed A0B5 & A0B0).
George

[Scottycs]

Socket visually looks okay, I am not sure how to open up the socket.

I did disconnect the climate at some point, could be the reason for the code.
I also removed and inspected JBE connections as well. Car starts perfectly normal, no issues.

I didn't have small enough connectors on my multimeter to test the wire continuity. I did check the power and grounds, all were good. I also checked the Can pins listed above and I got voltage readings on them as well.

I may be overthinking this, but could I have gotten 2 bad DSCs? I found a small sticker on the original DSC that was torn off "Rem." So it would appear that the module in there isn't original to the car. Though the used unit came off similar year car and matched the DSC part numbers.

Originally Posted by gbalthrop

I would suggest BEFORE opening up the E-box where DME is located, just remove the cover on the OTHER/Left side and disconnect the DSC Connector, X18303, and inspect pins & socket there.

Since this vehicle is "New-to-YOU", be aware that there is a distinct possibility that "Attilla the Automotive Electrocutor" worked on that car at some time in the past. Your DME Codes show:

Seven (7) "Botschaft" = Message faults, 5 of which relate to the DSC Module
Two Unknown Error Location faults, related to EWS4 & ECTS
Fuel Pump & IHKA "Messages" due to issue with bus communication.

While there are a number of rabbit-holes that may appear attractive, I would suggest focusing on WHY no communication with DSC, and WHY it does NOT appear on Fault Memory List (29 DSC). Since the BULK of the faults in other modules relate to "NO Message from DSC", that appears to be the logical place to start.

Does the engine start and run in relatively-normal fashion? If so, I presume the DME Fault related to DME Communication with EWS4 (12108 Decimal = 2F4C Hexadecimal = U0167), "NOT Currently Present", is NOT a factor. If there ARE currently issues related either to starter cranking or engine start, save & post any CAS module faults (you earlier showed A0B5 & A0B0).
George