Diagnostic Challenge - ECU? Wiring? Other?

After a long weekend that ultimately ended in me needing a rental car to get home, my avant is stuck 300 miles away with some unknown issue.

Little background: Last Friday I drove the car 300 miles to my sisters for the weekend with no problems (other than a loose PS hose clamp I noticed when I arrived). Sunday, I start the car and pull it around the house to the garage, shut it off, and load up some lumber from a project. Start the car again about 15min later and pull it back to the front of the house. Car started fine both times but had a bit of a lope/bobble to the idle, which I didn’t think much of as it had gone from 40deg to about 15deg and I just thought it was from sitting in the cold all night. I have no idea if that is related or not.

Anyway, a couple hours later I’ve got it loaded up and ready to head home and I went out to start it, and it just cranks and cranks. Sounds SO close to firing but just wouldn’t. If you ever had the crankshaft sensor go out it was very similar to that. BUT never threw a CEL (which the crank sensor does when it goes). In addition to the codes below, things of note:
1. With key in ON position, the front radiator fans run full blast. With key off, they shut off.
2. I don’t think the fuel pump is priming.

I hook up VCDS and get these codes. NOTE!!! It did NOT communicate with the Engine (Address 01). I could NOT get it to read anything in block 01.

Sunday,05,March,2017,11:45:15:29527
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64
VCDS Version: 17.1.3.0 (x64)
Data version: 20170203 DS267.2
www.Ross-Tech.com

VIN: WAUXL68E35A088128   License Plate: AVANT
Mileage: 224560km-139535mi   Repair Order: 

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Chassis Type: 8E (8E - Audi A4/S4/RS4 B6/B7 (2001 > 2008))
Scan: 01 02 03 08 09 0F 11 15 16 17 18 25 36 37 45 46 55 56 57 65
          67 69 75 76 77
 
VIN: WAUXL68E35A088128   Mileage: 224560km-139535miles
-------------------------------------------------------------------------------
Address 02: Auto Trans        Labels: 09L-927-760.lbl
   Part No SW: 8E0 910 156 R    HW: 09L 927 156 
   Component: AG6 09L 4.2L5V USA  0060  
   Revision: --H01---    Serial number:        0051534
   Coding: 0000002
   Shop #: WSC 06325 000 00000
   VCID: 35612E805F3221E90A-5140

1 Fault Found:
16946 - System Voltage 
            P0562 - 000 - Too Low - Intermittent
             Freeze Frame:
                    Fault Status: 00100000
                    Fault Priority: 0
                    Fault Frequency: 2
                    Reset counter: 40
                    Mileage: 224072 km
                    Time Indication: 0

             Freeze Frame:
                    RPM: 960 /min
                    RPM: 928 /min
                    RPM: 0 /min
                    (no units): 0.0
                    (no units): 22.0
                    Temperature: 25.0°C
                    T.B. Angle: 0.0°


-------------------------------------------------------------------------------
Address 03: ABS Brakes        Labels: 8E0-614-517.lbl
   Part No: 8E0 614 517 Q
   Component: ABS/ESP allrad      4533  
   Coding: 04597
   Shop #: WSC 06435  
   VCID: 3663298C12342AF103-5122

2 Faults Found:
18258 - Powertrain Data Bus 
            P1850 - 35-00 - Missing Message from ECU
18258 - Powertrain Data Bus 
            P1850 - 35-00 - Missing Message from ECU

-------------------------------------------------------------------------------
Address 08: Auto HVAC        Labels: 8E0-820-043.lbl
   Part No: 8E0 820 043 AD
   Component:   A4 Klimaautomat   1424  
   Coding: 00000
   Shop #: WSC 06325  
   VCID: 63C5A0D8F126EF5994-5140

3 Faults Found:
01172 - Temperature Sensor; Driver's Heated Seat (G59) 
            29-10 - Short to Ground - Intermittent
00819 - High Pressure Sensor (G65) 
            30-10 - Open or Short to Plus - Intermittent
00819 - High Pressure Sensor (G65) 
            07-10 - Signal too Low - Intermittent

-------------------------------------------------------------------------------
Address 09: Cent. Elect.        Labels: 8E0-907-279-8E2.lbl
   Part No: 8E0 907 279 F
   Component: int. Lastmodul  USA 0517  
   Coding: 01013
   Shop #: WSC 06325  
   VCID: 35612E800F3221E90A-4B1A

No fault code found.

-------------------------------------------------------------------------------
Address 0F: Digital Radio        Labels: 8E0-035-593-XM.lbl
   Part No: 8E0 035 593 A
   Component: SDAR XM            0010   
   VCID: 275DF4C8C59E437988-5074

1 Fault Found:
02635 - Tuner Not Enabled/Activated 
            35-00 -  - 

-------------------------------------------------------------------------------
Address 15: Airbags        Labels: 8E0-959-655-84.lbl
   Part No: 8E0 959 655 K
   Component: Airbag 8.4EP        1001  
   Coding: 0010607
   Shop #: WSC 06325 000 00000
   VCID: 3F8D4CA86D0EEBB9D0-515C

2 Faults Found:
01738 - Crash Sensor for Front Airbag; Drivers Side (G283) 
            011 - Open Circuit - Intermittent
01739 - Crash Sensor for Front Airbag; Pass. Side (G284) 
            011 - Open Circuit - Intermittent

-------------------------------------------------------------------------------
Address 16: Steering wheel        Labels: 8E0-953-549.lbl
   Part No: 8E0 953 549 N
   Component: Lenksáulenmodul     0611  
   Coding: 02042
   Shop #: WSC 06325  
   VCID: 3E7331AC3A04E2B1DB-4B1A

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments        Labels: 8E0-920-9xx-8E2.lbl
   Part No: 8E0 920 981 GX
   Component: KOMBI+WEGFAHRS. RB4 D42  
   Coding: 01201
   Shop #: WSC 09211  
   VCID: 09199270334A1509BE-5140
   WAUXL68E35A088128     AUZ6Z0D0278584

2 Faults Found:
00779 - Outside Air Temp Sensor (G17) 
            30-10 - Open or Short to Plus - Intermittent
01314 - Engine Control Module 
            49-00 - No Communications

-------------------------------------------------------------------------------
Address 36: Seat Mem. Drvr        Labels: 8E0-959-760.lbl
   Part No: 8E0 959 760 
   Component: Sitzmemory R2 F     0305  
   Coding: 00002
   Shop #: WSC 06325  
   VCID: 71E9DA903BDA4DC916-4AE8

No fault code found.

-------------------------------------------------------------------------------
Address 46: Central Conv.        Labels: 8E0-959-433-MAX.clb
   Part No: 8E0 959 433 BB
   Component: Komfortgerát T7B    1612  
   Coding: 12044
   Shop #: WSC 06325  
   VCID: 72EBD59C3EDC76D1EF-4B02

   Subsystem 1 - Part No: 8E1959801
   Component: Tõrsteuer.FS BRM 0205  

   Subsystem 2 - Part No: 8E1959802E
   Component: Tõrsteuer.BF BRM 0205  

   Subsystem 3 - Part No: 8E0959801A
   Component: Tõrsteuer.HL BRM 0205  

   Subsystem 4 - Part No: 8E0959802A
   Component: Tõrsteuer.HR BRM 0205  

12 Faults Found:
01701 - Dimmer for Interior Lighting 
            28-00 - Short to Plus
01565 - Luggage Compartment Light (W3) 
            28-10 - Short to Plus - Intermittent
00962 - Alarm via. Tilt Sensor 
            35-00 -  - 
01369 - Alarm triggered by Hood Switch 
            35-00 -  - 
01374 - Alarm triggered by Terminal 15 
            35-00 -  - 
01371 - Alarm triggered by Door Contact Switch; Driver's Side 
            35-00 -  - 
00956 - Key 2 
            35-10 -  -  - Intermittent
00957 - Key 3 
            35-10 -  -  - Intermittent
01702 - Footwell Lighting; Left (W9) 
            28-00 - Short to Plus
01703 - Footwell Lighting; Right (W10) 
            28-10 - Short to Plus - Intermittent
01696 - Footwell Lighting; Rear Left (W45) 
            28-00 - Short to Plus
01560 - Passenger Door 
            59-10 - Can't Unlock - Intermittent

-------------------------------------------------------------------------------
Address 55: Headlight Range        Labels: 4Z7-907-357.lbl
   Part No: 4Z7 907 357 
   Component: dynamische LWR       D09  
   Coding: 00060
   Shop #: WSC 06325  
   VCID: 0407834414684861CD-4B1A

No fault code found.

-------------------------------------------------------------------------------
Address 56: Radio        Labels: 8E0-035-1xx-56.lbl
   Part No: 8E0 035 195 H
   Component: symphony II PM6    0410   
   Coding: 01205
   Shop #: WSC 71936  
   VCID: 2C570BE4DC78602165-5074

No fault code found.

End-------------------------(Elapsed Time: 05:29)--------------------------

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                Address 17: Instruments  (8E0 920 981 GX)

11:52:57 Group 125: CAN-Databus Communication (Powertrain)
  Engine 0  Engine 
  Transm. 1  Transmission 
  ABS 1  Brake Electronics (J104)
       

So I do some fiddling, drop the belly pan back off, take the ECU cover off to see it if was wet (It wasn’t really, just some old leaves in there, and it hadn’t rained the night before or anything). Then I try autoscan again and get the following, and OH LOOK the engine block is back??? Wtf again. Note: I had not cleared anything after that first scan.

Sunday,05,March,2017,13:26:10:29527
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64
VCDS Version: 17.1.3.0 (x64)
Data version: 20170203 DS267.2
www.Ross-Tech.com


VIN: WAUXL68E35A088128   License Plate: 
Mileage: 224560km-139535mi   Repair Order: 



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


Chassis Type: 8E (8E - Audi A4/S4/RS4 B6/B7 (2001 > 2008))
Scan: 01 02 03 08 09 0F 11 15 16 17 18 25 36 37 45 46 55 56 57 65
          67 69 75 76 77
 
VIN: WAUXL68E35A088128   Mileage: 224560km-139535miles
-------------------------------------------------------------------------------
Address 01: Engine        Labels: 079-910-560-BBK.lbl
   Part No SW: 8E0 910 560 H    HW: 8E0 907 560 
   Component: 4.7L 93/\P      G   0010  
   Revision: 00000000    Serial number: AUZ6Z0D0278584
   Coding: 0007771
   Shop #: WSC 08167 444 83472
   VCID: 2A5B0DFC868C7E1197-515C

2 Faults Found:
18308 - Coolant Fan Control 2 
            P1900 - 004 - Open or Short to Ground
18080 - Coolant Fan Control 1 
            P1672 - 004 - Open or Short to Ground
Readiness: 0110 1101

-------------------------------------------------------------------------------
Address 02: Auto Trans        Labels: 09L-927-760.lbl
   Part No SW: 8E0 910 156 R    HW: 09L 927 156 
   Component: AG6 09L 4.2L5V USA  0060  
   Revision: --H01---    Serial number:        0051534
   Coding: 0000002
   Shop #: WSC 06325 000 00000
   VCID: 35612E805F3221E90A-515C

2 Faults Found:
16946 - System Voltage 
            P0562 - 000 - Too Low - Intermittent
             Freeze Frame:
                    Fault Status: 00100000
                    Fault Priority: 0
                    Fault Frequency: 2
                    Reset counter: 40
                    Mileage: 224072 km
                    Time Indication: 0

             Freeze Frame:
                    RPM: 960 /min
                    RPM: 928 /min
                    RPM: 0 /min
                    (no units): 0.0
                    (no units): 22.0
                    Temperature: 25.0°C
                    T.B. Angle: 0.0°

18170 - Shift Lock Solenoid (N110) 
            P1762 - 000 - Short to Plus - Intermittent
             Freeze Frame:
                    Fault Status: 00100000
                    Fault Priority: 0
                    Fault Frequency: 2
                    Reset counter: 40
                    Mileage: 224072 km
                    Time Indication: 0


-------------------------------------------------------------------------------
Address 03: ABS Brakes        Labels: 8E0-614-517.lbl
   Part No: 8E0 614 517 Q
   Component: ABS/ESP allrad      4533  
   Coding: 04597
   Shop #: WSC 06435  
   VCID: 3663298C12342AF103-5122

3 Faults Found:
18258 - Powertrain Data Bus 
            P1850 - 35-00 - Missing Message from ECU
01826 - Sensor for Steering Angle (G85); Supply Voltage Terminal 30 
            35-00 -  - 
18258 - Powertrain Data Bus 
            P1850 - 35-00 - Missing Message from ECU

-------------------------------------------------------------------------------
Address 08: Auto HVAC        Labels: 8E0-820-043.lbl
   Part No: 8E0 820 043 AD
   Component:   A4 Klimaautomat   1424  
   Coding: 00000
   Shop #: WSC 06325  
   VCID: 63C5A0D8F126EF5994-5140

4 Faults Found:
01172 - Temperature Sensor; Driver's Heated Seat (G59) 
            29-10 - Short to Ground - Intermittent
00819 - High Pressure Sensor (G65) 
            30-10 - Open or Short to Plus - Intermittent
00819 - High Pressure Sensor (G65) 
            07-10 - Signal too Low - Intermittent
01206 - Signal for Duration of Ignition Off Time 
            27-00 - Implausible Signal

-------------------------------------------------------------------------------
Address 09: Cent. Elect.        Labels: 8E0-907-279-8E2.lbl
   Part No: 8E0 907 279 F
   Component: int. Lastmodul  USA 0517  
   Coding: 01013
   Shop #: WSC 06325  
   VCID: 35612E800F3221E90A-4B1A

No fault code found.

-------------------------------------------------------------------------------
Address 0F: Digital Radio        Labels: 8E0-035-593-XM.lbl
   Part No: 8E0 035 593 A
   Component: SDAR XM            0010   
   VCID: 275DF4C8C59E437988-5090

1 Fault Found:
02635 - Tuner Not Enabled/Activated 
            35-00 -  - 

-------------------------------------------------------------------------------
Address 15: Airbags        Labels: 8E0-959-655-84.lbl
   Part No: 8E0 959 655 K
   Component: Airbag 8.4EP        1001  
   Coding: 0010607
   Shop #: WSC 06325 000 00000
   VCID: 3F8D4CA86D0EEBB9D0-515C

2 Faults Found:
01738 - Crash Sensor for Front Airbag; Drivers Side (G283) 
            011 - Open Circuit - Intermittent
01739 - Crash Sensor for Front Airbag; Pass. Side (G284) 
            011 - Open Circuit - Intermittent

-------------------------------------------------------------------------------
Address 16: Steering wheel        Labels: 8E0-953-549.lbl
   Part No: 8E0 953 549 N
   Component: Lenksáulenmodul     0611  
   Coding: 02042
   Shop #: WSC 06325  
   VCID: 3E7331AC3A04E2B1DB-4B02

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments        Labels: 8E0-920-9xx-8E2.lbl
   Part No: 8E0 920 981 GX
   Component: KOMBI+WEGFAHRS. RB4 D42  
   Coding: 01201
   Shop #: WSC 09211  
   VCID: 09199270334A1509BE-5140
   WAUXL68E35A088128     AUZ6Z0D0278584

3 Faults Found:
00779 - Outside Air Temp Sensor (G17) 
            30-10 - Open or Short to Plus - Intermittent
00668 - Supply Voltage Terminal 30 
            53-10 - Supply Voltage Too Low - Intermittent
01314 - Engine Control Module 
            49-10 - No Communications - Intermittent

-------------------------------------------------------------------------------
Address 36: Seat Mem. Drvr        Labels: 8E0-959-760.lbl
   Part No: 8E0 959 760 
   Component: Sitzmemory R2 F     0305  
   Coding: 00002
   Shop #: WSC 06325  
   VCID: 71E9DA903BDA4DC916-4B02

1 Fault Found:
00668 - Supply Voltage Terminal 30 
            07-10 - Signal too Low - Intermittent

-------------------------------------------------------------------------------
Address 46: Central Conv.        Labels: 8E0-959-433-MAX.clb
   Part No: 8E0 959 433 BB
   Component: Komfortgerát T7B    1612  
   Coding: 12044
   Shop #: WSC 06325  
   VCID: 72EBD59C3EDC76D1EF-4B02

   Subsystem 1 - Part No: 8E1959801
   Component: Tõrsteuer.FS BRM 0205  

   Subsystem 2 - Part No: 8E1959802E
   Component: Tõrsteuer.BF BRM 0205  

   Subsystem 3 - Part No: 8E0959801A
   Component: Tõrsteuer.HL BRM 0205  

   Subsystem 4 - Part No: 8E0959802A
   Component: Tõrsteuer.HR BRM 0205  

12 Faults Found:
01701 - Dimmer for Interior Lighting 
            28-00 - Short to Plus
01565 - Luggage Compartment Light (W3) 
            28-10 - Short to Plus - Intermittent
00962 - Alarm via. Tilt Sensor 
            35-00 -  - 
01369 - Alarm triggered by Hood Switch 
            35-00 -  - 
01374 - Alarm triggered by Terminal 15 
            35-00 -  - 
01371 - Alarm triggered by Door Contact Switch; Driver's Side 
            35-00 -  - 
00956 - Key 2 
            35-10 -  -  - Intermittent
00957 - Key 3 
            35-10 -  -  - Intermittent
01702 - Footwell Lighting; Left (W9) 
            28-00 - Short to Plus
01703 - Footwell Lighting; Right (W10) 
            28-10 - Short to Plus - Intermittent
01696 - Footwell Lighting; Rear Left (W45) 
            28-10 - Short to Plus - Intermittent
01560 - Passenger Door 
            59-10 - Can't Unlock - Intermittent

-------------------------------------------------------------------------------
Address 55: Headlight Range        Labels: 4Z7-907-357.lbl
   Part No: 4Z7 907 357 
   Component: dynamische LWR       D09  
   Coding: 00060
   Shop #: WSC 06325  
   VCID: 0407834414684861CD-4B1A

1 Fault Found:
00532 - Supply Voltage B+ 
            07-10 - Signal too Low - Intermittent

-------------------------------------------------------------------------------
Address 56: Radio        Labels: 8E0-035-1xx-56.lbl
   Part No: 8E0 035 195 H
   Component: symphony II PM6    0410   
   Coding: 01205
   Shop #: WSC 71936  
   VCID: 2C570BE4DC78602165-5090

No fault code found.

End-------------------------(Elapsed Time: 05:24)--------------------------

I had a battery charger on it sometime between the two reads with a few start attempts as well. All the airbag sensors and radiator stuff is plugged in.

My thoughts are a bad ground or power wire loose or a short somewhere? Or is my ECU cooked? I found a B6 A4 thread where someone had the same issue with no pump prime, fans blowing with key on, and no-start… ended up being a bad ECU I guess. Idk if that is my case, but it seems like something weird is going on specifically with a lot of the codes being from front end/radiator wiring, since I have fans acting up, the outdoor air temp sensor is on there, front airbag sensors, etc. Not sure with the transmission stuff, I know I am about 1/2 qt low on fluid since I had the front clip off and installed the jhm cooler last week, but it drove about 400-500 miles since then without issue so I don’t know??

Unfortunately I didn’t have much time to mess around as I needed to get home and had to find a rental and drive 5 hours still. Does anything jump out at anyone? Just wondering if someone has any sort of experience with this or can at least give something to look into once I get the car home.

Help me [=(] [confused]

I posted on AZ as well, so far I’ve got another opinion that the fans means a cooked ECU, but also that it still might be a short/wire/ground/power issue. So my main question in addition the above ones- are there any resources available to help troubleshoot something like this? Something that helps indicate what relay or pins to test, what voltage to expect in what scenario, or stuff like that. I have the Bentley but am willing to get something else as well.

Thanks