Unknown VCDS codes 37931 and 37932

[Dsmart]

I have having some ongoing issues with my 2014 Q7 TDI that trigger a limp mode and occasionally an engine MIL. My scanner seems to be missing the ROD files to read the engine module. There are 4 engine codes that appear 31982/31983 which appear to be related to the EGR and 37931/37932 which I cannot cross reference to anything. My guess is the EGR valve is not closing properly and causing a low boost condition which triggers the limp. It would be nice to confirm that which is why I would like to identify those other 2 mystery codes to prove my theory on the low boost. I am about to install an EGR delete/malone stage2 w/DPF,EGR etc etc but would like to be sure I clear all issues prior to installing. If anyone could shed some light on the meaning of those 2 codes it would be very helpful. Thanks

 

[gforce1108]

Not under the extended warranty still?

 

[TurboABA]

I don't recognize that format of codes.... what tool are you using to pull those?
Is there any other info?

 

[joep1234]

I don't remember what VAGCOM codes my wife's had but it was for the EGR. It is still under warranty with just 60k on the clock. when I got it back they said it wasn't the EGR valve but was the EGR controller. 10k and no problems except it uses twice the DEF fluid that my Q5 does. Mine has 100k on it and used 2.5 gallons in 11k miles. I topped off my wife's with 7k miles and it took almost 4 gallons. Plus a little savings, buy your DEF fluid at the VW dealership. The 1/2 gallon bottle was $5.39 including tax and the 2.5 gallon jug is $10. Audi was 3 times more than that and they are 1 mile apart.

 

[gforce1108]

I don't remember what VAGCOM codes my wife's had but it was for the EGR. It is still under warranty with just 60k on the clock. when I got it back they said it wasn't the EGR valve but was the EGR controller. 10k and no problems except it uses twice the DEF fluid that my Q5 does. Mine has 100k on it and used 2.5 gallons in 11k miles. I topped off my wife's with 7k miles and it took almost 4 gallons. Plus a little savings, buy your DEF fluid at the VW dealership. The 1/2 gallon bottle was $5.39 including tax and the 2.5 gallon jug is $10. Audi was 3 times more than that and they are 1 mile apart.

DEF refills are supposed to be free with the emissions warranty. I grabbed it wherever it was convenient. Walmart/Advance auto, it's all the same.

 

[joep1234]

Only when you use more than a tank full before your usual 10K oil change. At the VW dealership it is $10 US for 2.5 gallons and there is a part number for the adapter to use the bulk container for $26.

 

[Dsmart]

I don't recognize that format of codes.... what tool are you using to pull those?
Is there any other info?

Hey, for some reason I never got a notification that someone responded to my thread. I was using a really old knockoff Vagcom cable at the time but ordered a new one that now reads the codes. I have since installed the egr delete plates and malone tune...etc bu the limp mode problem remains. The issue is compounded by the fact that now I do not get a CEL when the limp mode occurs and there are no faults logged. I believe this is due to the tune so I am really flying blind here. The limp seems to be triggered while decelerating or waiting at a light...it never happens under load or aggressive driving.

I've actually read through afew of your posts regarding temp sensors which originally I had thought might be causing my issue. After learning more about how the system works (thanks to your threads) and some data logging I do not think that is my issue. Not sure where to go on this one right now. I've done many logs and cannot seem to find anything that looks funky. You would think something severe enough to cause a limp mode event would always result in a fault code being logged...apparently not!

 

[Dsmart]

Tuesday,30,November,2021,16:27:42:62939
VCDS -- Windows Based VAG/VAS Emulator
VCDS Version: Release 12.12.0 (x64)
Data version: 20130910


VIN: WA1DMCFE0ED006207 License Plate:



--------------------------------------------------------------------------------
--------------------------------------------------------------------------------


Address 01: Engine Labels: None
Control Module Part Number: 4L2 910 401 A HW: 4L0 907 401 E
Component and/or Version: 3.0TDI FSA H23 0014
Software Coding: 2A2A4012253600050000
Work Shop Code: WSC 58640 001 1048576
ASAM Dataset: EV_ECM30TDI0114L2910401A 001015 (AU56)
VCID: 224B0C03353A2A0EA27-8077
2 Faults Found:

31982 - ROD - Unknown Error Code
- 00 [096]
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 259595 km
Date: 2021.11.30
Time: 15:05:03

31983 - ROD - Unknown Error Code
- 00 [096]
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 259595 km
Date: 2021.11.30
Time: 15:05:03


Readiness: 0 0 0 1 1

 

[TurboABA]

Seems like you're using VCDS mobile.... I'm not too familiar with its fanciness, but I believe there's an "update" requirement once you do the initial autoscan to pickup all the ROD and ASAM files using the config utility while connected to a PC....

 

[TurboABA]

Something like this

 

[TurboABA]

Tuesday,30,November,2021,16:27:42:62939
VCDS -- Windows Based VAG/VAS Emulator
VCDS Version: Release 12.12.0 (x64)
Data version: 20130910

You are attempting to work with a super old dataset!

The Current version is:
Release 22.3.1
Data Version 20220407 / DS337.0

 

[Dsmart]

Yes that's what I figured. It was an old cable I had from back in my PD days which worked on all my newer vehicles until VW put the emissions update on the Q7. I have a new cable now that will read everything but since I had already installed the tune I no longer get a CEL or logged faults when the limp mode occurs. Last night I put the stock ECU file back on the Q7 and will drive it around until I goes into limp. Hopefully the CEL will come on and there will be some sort of fault logged. I drove to work this morning and took a snapshot of the codes that were present due to the lack of egr flow and all the emission/exhaust stuff being removed but of course it did not go into limp like it normally would. I thought for sure it would go into limp mode just with all the stuff disconnected but it actually drove pretty nice. Maybe the issue is in the tune that I got from Malone....time will tell.

 

[TurboABA]

I doubt the interface was the issue.... I'm still using an RS-232 unit from way back on my '14 egg but with up to date software\config and it works just fine.

 

[Dsmart]

I doubt the interface was the issue.... I'm still using an RS-232 unit from way back on my '14 egg but with up to date software\config and it works just fine.

The old interface would work for most stuff on the car but was "missing ROD" files when I would scan the Engine. I tried to use it with a newer version of VCDS but it had some sort of compatibility error and would not connect. I bought the latest version (knockoff) and it works great for everything. Before I had the emissions update the old interface would scan and read the engine so I just assumed that whatever was involved with the emissions software made it obsolete.

 

[TurboABA]

You just explained your own problem.

(knockoff)

As I've shown you above, the firmware\software being used is 9 years old......

 

[Dsmart]

You just explained your own problem.


As I've shown you above, the firmware\software being used is 9 years old......

Yes the issue with my interface was solved some time ago with the purchase of a new one. Now that I have the original file back in the ECU im hoping when the limp mode happens ill be able to identify the source of the problem. If there is a problem with the EGR valve I would have thought that an EGR delete (hardware and software) would have resolved it but perhaps I am mistaken.

 

[TurboABA]

You can guess at what the issue might be for a long time.... unfortunately you're using a diagnostic tool that's giving you useless codes, so you are still doing it blindly. I'm not sure why you're suspecting VAG or Malone when your China tool is giving you information that can't be interpreted....

I wouldn't risk troubleshooting "this way", but I'm not you.... maybe you will see something when you go into limp mode... maybe you'll hurt something.... gutsy approach in my opinion.

 

[Dsmart]

You can guess at what the issue might be for a long time.... unfortunately you're using a diagnostic tool that's giving you useless codes, so you are still doing it blindly. I'm not sure why you're suspecting VAG or Malone when your China tool is giving you information that can't be interpreted....

I wouldn't risk troubleshooting "this way", but I'm not you.... maybe you will see something when you go into limp mode... maybe you'll hurt something.... gutsy approach in my opinion.

I think we are missing each other on this one.

1. My old interface would not pull up a detailed code...I replaced it with a new interface that will pull up detailed codes
2. Before I the new interface came in I install my tune/deletes which I was hoping would eliminate the issue which I believed was due to a faulty EGR
3. New interface came in but with the tune/deletes installed my vehicle no longer registers a CEL or logs any faults when going into limp mode

I do not think the the tune is the issue I was merely speculating that the EGR delete portion of the tune might not be working correctly. I have reached out to Malone to confirm that the tune is correct so I can rule that out as being the issue. I understand that I am using a knockoff interface but the new one works very well and without the tune supressing the CEL and fault codes I will certainly be able to pull up some detailed info when the limp occurs next.

The set of circumstances in this case has certainly complicated the troubleshooting process. If I had the proper interface from the beginning than I would have been able to interpret the fault before installed the tune. I know very well the value of a genuine vagcom interface and have driven VAG products long enough to have justified the purchase over a decade ago and yet I haven't bought one. All I can do now is wait for the limp mode to come back and go from there.

 

[TurboABA]

We just have different perspective on the matter.
I'm saying, that I am uncomfortable being "blind" when dealing with a code that puts me into limp mode.
To me, anything that throws me into limp is the ECU's way of saving me from damaging stuff.

It also appears that you didn't clearly indicate (or I missed the fact) that you were posting OLD codes, not current ones from your new interface.

Tuesday,30,November,2021

It's nice that you might've addressed the issue with your deletes.....

So are you saying that your new scans show the update data instead of the scan you've been showing?

VCDS Version: Release 12.12.0

 

[Dsmart]

Yes you are right, I re-posted the original scan I did months ago when this problem first appeared. I should have been more specific about that as it certainly has confused our conversation. I managed to get the vehicle into limp mode last night and was able to pull up the codes. The top 6 are ones that came up shortly after the engine was started (due to deletes and missing parts) but the bottom 2 are specific to the limp mode. As suspected the EGR valve is faulty and even with the "EGR delete" tune still puts the car into limp. I spoke with Malone tuning and they suggested I remove the plug on the EGR valve and see it that fixes the problem.

I just finished pulling the intake manifold,EGR and oil cooler to replace the gaskets down there and when I looked at the EGR valve is was surprisingly clean...I expected it to be all sooted up.


Wednesday,20,April,2022,16:49:02:00009
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64
VCDS Version: 21.9.0.2 (x64)
Data version: 20210903 DS330.0
www.Ross-Tech.com


VIN: WA1DMCFE0ED006207 License Plate: VVV2



--------------------------------------------------------------------------------
--------------------------------------------------------------------------------


Address 01: Engine Labels: 059-907-401-V2.clb
Control Module Part Number: 4L2 910 401 A HW: 4L0 907 401 E
Component and/or Version: 3.0TDI FSA H23 0014
Software Coding: 2A2A4012253600050000
Work Shop Code: WSC 00000 000 00000
ASAM Dataset: EV_ECM30TDI0114L2910401A 001015 (AU56)
ROD: EV_ECM30TDI0114L2910401A.rod
VCID: 224B5F8F35CFF89977-8076
9 Faults Found:

4807 - EGR System
P0401 00 [237] - Insufficient Flow
[New feature! Extended UDS fault detail is only supported by current gen. interfaces]
MIL ON - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 265882 km
Date: 2022.04.18
Time: 20:53:34

Engine RPM: 778.00 /min
Normed load value: 31.8 %
Vehicle speed: 0 km/h
Coolant temperature: 47 °C
Intake air temperature: 15 °C
Ambient air pressure: 980 mbar
Voltage terminal 30: 13.140 V
Unlearning counter according OBD: 40
Mean injection quantity: 9.66 mg/stroke
Control Module temperature: 24.7 °C
EGR_governor_deviation: -149.9 mg/stroke
Inj Ctl q Curr: 9.56 mg/stroke
Standardized air flow ratio: 1.0835
Air mass at air mass meter 1: 62.2 kg/h
Actual charge pressure: 981 hPa

16551 - EGR during Cold Start
P04DD 00 [175] - Insufficient Flow
[New feature! Extended UDS fault detail is only supported by current gen. interfaces]
MIL ON - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 265907 km
Date: 2022.04.19
Time: 15:10:02

Engine RPM: 1418.00 /min
Normed load value: 29.0 %
Vehicle speed: 41 km/h
Coolant temperature: 36 °C
Intake air temperature: 11 °C
Ambient air pressure: 990 mbar
Voltage terminal 30: 14.300 V
Unlearning counter according OBD: 40
Mean injection quantity: 11.06 mg/stroke
Control Module temperature: 15.8 °C
EGR_governor_deviation: -276.6 mg/stroke
Inj Ctl q Curr: 10.96 mg/stroke
Standardized air flow ratio: 1.1846
Air mass at air mass meter 1: 146.2 kg/h
Actual charge pressure: 1290 hPa

20199 - Reductant Tank Cap Switch
P24CB 00 [032] - Electrical Malfunction
[New feature! Extended UDS fault detail is only supported by current gen. interfaces]
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 265882 km
Date: 2022.04.18
Time: 20:53:01

Engine RPM: 0.00 /min
Normed load value: 0.0 %
Vehicle speed: 0 km/h
Coolant temperature: 52 °C
Intake air temperature: 22 °C
Ambient air pressure: 980 mbar
Voltage terminal 30: 12.020 V
Unlearning counter according OBD: 40
Outside temperature: 4.5 °C
Pressure sensor for reducing agent: measured pressure: 4 hPa
Mean temperature of SCR catalyst: 17.9 °C
Sensor for reducing agent tank temperature: temperature: 4.6 °C
Reducing agent pump: activation: 90.00 %
Calculated temperature at reduction agent injection valve: -0.0 °C

20179 - No Communications with Particulate Sensor
U02A3 00 [175] - -
MIL ON - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 265882 km
Date: 2022.04.18
Time: 20:52:56

Engine RPM: 0.00 /min
Normed load value: 0.0 %
Vehicle speed: 0 km/h
Coolant temperature: 52 °C
Intake air temperature: 22 °C
Ambient air pressure: 980 mbar
Voltage terminal 30: 11.940 V
Unlearning counter according OBD: 40
Limitation: accelerator pedal: 0.0 Nm
CAN status - engine control module-Bits 0-7: 0
Cruise Control System (CCS): status-Bits 0-7: 44
CAN status - transmission control module-Bits 0-7: 0
CAN status - brake control module 1-Bits 0-7: 0
CAN status - brake control module 2-Bits 0-7: 0
selected gear-Bits 0-7: 0

18195 - No Communications with Particulate Sensor
U02A3 00 [175] - -
MIL ON - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 265882 km
Date: 2022.04.18
Time: 20:52:56

Engine RPM: 0.00 /min
Normed load value: 0.0 %
Vehicle speed: 0 km/h
Coolant temperature: 52 °C
Intake air temperature: 22 °C
Ambient air pressure: 980 mbar
Voltage terminal 30: 11.940 V
Unlearning counter according OBD: 40
Limitation: accelerator pedal: 0.0 Nm
CAN status - engine control module-Bits 0-7: 0
Cruise Control System (CCS): status-Bits 0-7: 44
CAN status - transmission control module-Bits 0-7: 0
CAN status - brake control module 1-Bits 0-7: 0
CAN status - brake control module 2-Bits 0-7: 0
selected gear-Bits 0-7: 0

25301 - EGR Temperature Sensor 1
P040B 00 [237] - Implausible Signal
MIL ON - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 265883 km
Date: 2022.04.19
Time: 07:37:11

Engine RPM: 1770.50 /min
Normed load value: 38.8 %
Vehicle speed: 48 km/h
Coolant temperature: 26 °C
Intake air temperature: 3 °C
Ambient air pressure: 990 mbar
Voltage terminal 30: 14.340 V
Unlearning counter according OBD: 40
Engine status: COENG_RUNNING
Engine status-Test_Program_Co Eng st COMPU VERB UBYTE: 3

19406 - Exhaust Gas Recirculation Cooler Bypass Control Circuit
P245B 00 [101] - Implausible Signal
[New feature! Extended UDS fault detail is only supported by current gen. interfaces]
Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 265904 km
Date: 2022.04.19
Time: 07:56:38

Engine RPM: 1558.50 /min
Normed load value: 37.6 %
Vehicle speed: 78 km/h
Coolant temperature: 89 °C
Intake air temperature: 5 °C
Ambient air pressure: 980 mbar
Voltage terminal 30: 14.760 V
Unlearning counter according OBD: 40
EGR Clg t Egr Ds De Mon Heat Avg: -58.8 K
EGR Clg dm Egr Mon Heat Avg: 39.6 kg/h
EGR Clg t Turbn Us Mon Avg: 378.5 °C
Air t EGR Clr Ds: 79.6 °C
Air mass: actual value (mg/stroke): 441.6 mg/stroke
EGR Vacuum Regulator Solen.val.: activation: 15.00 %
Outside temperature: -1.0 °C

37931 - EGR Valve (N18)
P0403 00 [036] - Malfunction
[New feature! Extended UDS fault detail is only supported by current gen. interfaces]
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 265907 km
Date: 2022.04.19
Time: 15:10:34

Engine RPM: 889.00 /min
Normed load value: 0.0 %
Vehicle speed: 23 km/h
Coolant temperature: 39 °C
Intake air temperature: 11 °C
Ambient air pressure: 990 mbar
Voltage terminal 30: 14.520 V
Unlearning counter according OBD: 40
EGR Vlv i Eff Flt: 79.76 A
EGR Vacuum Regulator Solen.val.: activation: 100.00 %
EGR Solen.val.: actual value: 95.81 %
EGR valve: offset closed: 2.14 %
High press EGR actuator: actual unconditioned volt val: 850.2 mV
EGR valve: offset open: -2.14 %

37932 - EGR Valve (N18)
P0403 00 [036] - Malfunction
[New feature! Extended UDS fault detail is only supported by current gen. interfaces]
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 265907 km
Date: 2022.04.19
Time: 15:10:34

Engine RPM: 984.00 /min
Normed load value: 0.0 %
Vehicle speed: 24 km/h
Coolant temperature: 39 °C
Intake air temperature: 11 °C
Ambient air pressure: 990 mbar
Voltage terminal 30: 14.480 V
Unlearning counter according OBD: 40
EGR Vlv i Eff Flt: 79.84 A
EGR Vacuum Regulator Solen.val.: activation: 0.00 %
EGR Solen.val.: actual value: 17.76 %
EGR valve: offset closed: 2.14 %
High press EGR actuator: actual unconditioned volt val: 3528.6 mV
EGR valve: offset open: -2.14 %


Readiness: 1 5 0 1 0

 

[TurboABA]

When you say you "deleted" the EGR.... what do you actually mean? Like you blocked off the turbo\intake ports and bypassed the cooler?
I'm a little thrown off by the N18 codes.... is there an N18 on your engine?

 

[Dsmart]

I bought a kit from darkside developments that removes the pipe from the outlet on EGR valve to the intake manifold and uses 2 block off plates. I wanted to physically block off the EGR incase the valve was hanging open. An added bonus is that you get to remove the insert in the intake pipe that significantly blocks airflow.
The EGR valve/cooler assembly was physically left in place as the "cooler bypass kit" is ridiculously expensive. I was alittle thrown off by the N18 also but I believe that is in reference to the actual EGR valve itself. On vacuum controlled EGR valves the N18 is usually the control solenoid but as this EGR is electronic perhaps they just keep the same description and use it for the EGR valve/motor component.??
I uploaded the tune back into the Q7 last night and removed the connector from the EGR valve and did not get a limp mode on my way to work this morning. I'll have to give it another day or so to be sure but things are looking good so far.

 

[TurboABA]

So you're actually unplugging the "Exhaust gas recirculation control motor V338" and interpreting your code as calling this an N18?
I would suspect that your tune needs to fake or eliminate the readings that would come from the V338, G98 & the pneumatic lift valve in order to keep the ECU from throwing you into limp mode.

 

[Dsmart]

I would assume that the Malone EGR delete would include whatever is necessary to stop the EGR from functioning without throwing a code. They explained to me that a "previously failed" EGR valve might still cause issues if it is still plugged in. They also suggest this for the DPF pressure sensor as well. I see what you mean about the discrepancy between the N18 and V338.

They did not specify if I should be disconnecting the V338 or the vacuum solenoid which controls the EGR cooler bypass valve. I made the assumption that they wanted me to disconnect the EGR motor.

 

[TurboABA]

So in your case, is your V338 not cycling? It looks like the voltage is changing but the offsets are not.

 

[Dsmart]

I'm not sure what a functioning one would show but it does appear that voltage change does not correspond with a change in offset. I wasn't sure if "offset" was in reference to the valve position.

 

[TurboABA]

Check wiring diagrams.... to me it looks like the egr motor and turbo module share two signals, so that could be adding to your issues if it's not seeing the correct fluctuation\resistance from being physically jammed and\or disconnected.

 

[Dsmart]

Well into day 2 of "limp mode" free driving. It looks like there are some failure modes of the EGR that are not isolated by a software delete but make troubleshooting with the delete tune in place very difficult as the codes/CEL are suppressed. The silver lining (in my case) is that the solution is to simply disconnect the connector to the EGR motor which is still accessible with the intake manifold in place on a CNRB....not sure about previous generations. I'll have to give it afew more days but going from 2-3 limp events per trip down to 0 limps in multiple trips has me almost convinced.