A3 2.0 TDI 170 No start

[DrSkoff]

Hope someone is able to help. Car was running fine with no issues, was then left for a coupl of months. When I went back to it, it wouldn't start. Battery was fully charged, still nothing. Dahboard lights up, message says 'Igniition is on', also ABS error message.

Have replaced battery, ignition switch, fuses, under bonnet main relay, under dash relays and Body Control Module under the dash. Any help would be greatly appreciated.

VCDS diagnostic below.

Chassis Type: 8P (1K0)
Scan: 01 03 08 09 15 16 17 19 22 25 42 44 46 47 52 56 62 72

VIN: WAUZZZ8P7AA144642   Mileage: 196460km-122074miles

01-Engine -- Status: Cannot be reached 1100
03-ABS Brakes -- Status: Cannot be reached 1100
04-Steering Angle -- Status: Cannot be reached 1100
08-Auto HVAC -- Status: Malfunction 0010
09-Cent. Elect. -- Status: Malfunction 0010
15-Airbags -- Status: Cannot be reached 1100
16-Steering wheel -- Status: OK 0000
17-Instruments -- Status: Malfunction 0010
19-CAN Gateway -- Status: OK 0000
22-AWD -- Status: Cannot be reached 1100
25-Immobilizer -- Status: OK 0000
42-Door Elect, Driver -- Status: OK 0000
44-Steering Assist -- Status: Cannot be reached 1100
46-Central Conv. -- Status: OK 0000
47-Sound System -- Status: OK 0000
52-Door Elect, Pass. -- Status: OK 0000
56-Radio -- Status: OK 0000
62-Door, Rear Left -- Status: OK 0000
72-Door, Rear Right -- Status: OK 0000
-------------------------------------------------------------------------------
Address 01: Engine
Cannot be reached

-------------------------------------------------------------------------------
Address 03: ABS Brakes
Cannot be reached

-------------------------------------------------------------------------------
Address 08: Auto HVAC        Labels: 8P0-820-043.lbl
   Part No SW: 8P0 820 043 BM    HW: 8P0 820 043 BM
   Component: KlimavollautomatH09 0150  
   Revision: 000854      Serial number: 8P0820043BM   
   Shop #: WSC 00000 000 00000
   VCID: 78A9E69BDED5D43A67B-802C

3 Faults Found:
01592 - Air Quality Sensor (G238) 
            007 - Short to Ground
             Freeze Frame:
                    Fault Status: 01100111
                    Fault Priority: 3
                    Fault Frequency: 254
                    Reset counter: 7
                    Mileage: 174384 km
                    Time Indication: 0
                    Date: 2021.03.31
                    Time: 17:52:12

             Freeze Frame:
                    Temperature: 19.5°C

00819 - High Pressure Sensor (G65) 
            009 - Open or Short to Ground
             Freeze Frame:
                    Fault Status: 01101001
                    Fault Priority: 3
                    Fault Frequency: 6
                    Reset counter: 7
                    Mileage: 196462 km
                    Time Indication: 0
                    Date: 2024.04.05
                    Time: 11:45:59

             Freeze Frame:
                    Temperature: 15.5°C
                    Voltage: 12.00 V
                    RPM: 0 /min
                    Load: 0.0 %
                    Load: 0.0 %

01206 - Signal for Duration of Ignition Off Time 
            008 - Implausible Signal
             Freeze Frame:
                    Fault Status: 01101000
                    Fault Priority: 3
                    Fault Frequency: 1
                    Reset counter: 7
                    Mileage: 196462 km
                    Time Indication: 0
                    Date: 2024.07.12
                    Time: 00:01:26

             Freeze Frame:


-------------------------------------------------------------------------------
Address 09: Cent. Elect. (J519)       Labels:. 8P0-907-063.clb
   Part No SW: 8P0 907 063 A    HW: 8P0 907 063 A
   Component: BCM PQ35  M   105 0575  
   Revision: 00105 AK    
   Coding: 0E000A2FB005F0C0207041E00000015C431A29AA104DC129E40008800040
   Shop #: WSC 06314 000 00000
   VCID: 323D14B37429FE6A99F-8066

   Subsystem 1 - Part No SW: 8P2 955 119 F    HW: 8P2 955 119 F  Labels: 1KX-955-119.CLB
   Component: Wischer AU350  H10 0040 
   Coding: 00DD13

   Subsystem 2 - Part No: 8P0 951 177 
   Component: Innenraumuebe  H04 0020 

   Subsystem 3 - Part No: 1K0 951 605 C
   Component: LIN BACKUP HO  H05 1501 

   Subsystem 4 - Part No: 1K0 907 719 C
   Component: Neigungssenso  005 0003 


00778 - Steering Angle Sensor (G85) 
            004 - No Signal/Communication
             Freeze Frame:
                    Fault Status: 01100100
                    Fault Priority: 6
                    Fault Frequency: 1
                    Reset counter: 7
                    Mileage: 196462 km
                    Time Indication: 0
                    Date: 2024.07.12
                    Time: 00:02:55

             Freeze Frame:
                        Term 15 On
                    Voltage: 12.00 V
                        ON
                        ON
                        Term 50 Off
                        OFF
                        OFF

01309 - Power Steering Control Module (J500) 
            004 - No Signal/Communication
             Freeze Frame:
                    Fault Status: 01100100
                    Fault Priority: 6
                    Fault Frequency: 1
                    Reset counter: 7
                    Mileage: 196462 km
                    Time Indication: 0
                    Date: 2024.07.12
                    Time: 00:02:55

             Freeze Frame:
                        Term 15 On
                    Voltage: 12.00 V
                        ON
                        ON
                        Term 50 Off
                        OFF
                        OFF

01314 - Engine Control Module 
            004 - No Signal/Communication
             Freeze Frame:
                    Fault Status: 01100100
                    Fault Priority: 6
                    Fault Frequency: 1
                    Reset counter: 7
                    Mileage: 196462 km
                    Time Indication: 0
                    Date: 2024.07.12
                    Time: 00:02:55

             Freeze Frame:
                        Term 15 On
                    Voltage: 12.00 V
                        ON
                        ON
                        Term 50 Off
                        OFF
                        OFF

01316 - ABS Control Module 
            004 - No Signal/Communication
             Freeze Frame:
                    Fault Status: 01100100
                    Fault Priority: 6
                    Fault Frequency: 1
                    Reset counter: 7
                    Mileage: 196462 km
                    Time Indication: 0
                    Date: 2024.07.12
                    Time: 00:02:55

             Freeze Frame:
                        Term 15 On
                    Voltage: 12.00 V
                        ON
                        ON
                        Term 50 Off
                        OFF
                        OFF

01321 - Control Module for Airbags (J234) 
            004 - No Signal/Communication
             Freeze Frame:
                    Fault Status: 01100100
                    Fault Priority: 6
                    Fault Frequency: 1
                    Reset counter: 7
                    Mileage: 196462 km
                    Time Indication: 0
                    Date: 2024.07.12
                    Time: 00:02:55

             Freeze Frame:
                        Term 15 On
                    Voltage: 12.00 V
                        ON
                        ON
                        Term 50 Off
                        OFF
                        OFF


-------------------------------------------------------------------------------
Address 15: Airbags
Cannot be reached

-------------------------------------------------------------------------------
Address 16: Steering wheel        Labels: 8P0-953-549.lbl
   Part No SW: 8P0 953 549 K    HW: 8P0 953 549 K
   Component: J0527           H37 0070  
   Coding: 0002012
   Shop #: WSC 06314 000 00000
   VCID: 46D55863E4A172CA257-8012

   Subsystem 1 - Part No: XXXXXXXXXXX 
   Component: E0221           H04 0100

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments        Labels: 8P0-920-xxx-17-MY8.clb
   Part No SW: 8P0 920 982 J    HW: 8P0 920 982 J
   Component: KOMBIINSTR. VDO H03 0990  
   Revision: D0H03005    Serial number: 2242J005020738
   Coding: 0005428
   Shop #: WSC 12345 123 12345
   VCID: 40D94E7BC6855CFA1FB-8014

1 Fault Found:
00562 - Sensor for Oil Level/Temperature (G266) 
            010 - Open or Short to Plus
             Freeze Frame:
                    Fault Status: 01101010
                    Fault Priority: 6
                    Fault Frequency: 1
                    Reset counter: 7
                    Mileage: 196462 km
                    Time Indication: 0
                    Date: 2024.07.12
                    Time: 00:02:56


-------------------------------------------------------------------------------
Address 19: CAN Gateway        Labels:. 1K0-907-530-V4.clb
   Part No SW: 1K0 907 530 AD    HW: 1K0 907 951 
   Component: J533  Gateway   H16 0233  
   Revision:   H16       Serial number: 4520K102250230
   Coding: E9827F06100202002103
   Shop #: WSC 06314 000 00000
   VCID: 698FB3DF957F7DB2E85-803C

No fault code found.

-------------------------------------------------------------------------------
Address 22: AWD
Cannot be reached

-------------------------------------------------------------------------------
Address 25: Immobilizer        Labels: 1K0-920-xxx-25.clb
   Part No SW: 8P0 920 982 J    HW: 8P0 920 982 J
   Component: KOMBIINSTR. VDO H03 0990  
   Revision: D0H03005    Serial number: AUX7Z0J2FN406X
   Shop #: WSC 00000 000 00000
   VCID: 40D94E7BC6855CFA1FB-8014

No fault code found.

-------------------------------------------------------------------------------
Address 42: Door Elect, Driver        Labels: 8P0-959-801-MIN3.lbl
   Part No SW: 8P0 959 801 N    HW: 8P0 959 801 N
   Component: Tuer-SG         H04 0100  
   Coding: 0000692
   Shop #: WSC 06314 000 00000
   VCID: 46D55863E4A172CA257-8012

No fault code found.

-------------------------------------------------------------------------------
Address 44: Steering Assist
Cannot be reached

-------------------------------------------------------------------------------
Address 47: Sound System        Labels: 8Px-035-382.lbl
   Part No SW: 8P4 035 382 E    HW: 8P4 035 382 E
   Component: AB2 SUBWOOFERBOXH07 0180  
   Revision: 00006       Serial number: 92158067869366
   Shop #: WSC 00000 000 00000
   VCID: 363528A39441E24AB57-8062

No fault code found.

-------------------------------------------------------------------------------
Address 52: Door Elect, Pass.        Labels:. 1K0-959-702-MIN3.clb
   Part No SW: 8P0 959 802 N    HW: 8P0 959 802 N
   Component: Tuer-SG         H04 0100  
   Coding: 0000692
   Shop #: WSC 06314 000 00000
   VCID: 47CB5567E3AB6BC2DE1-8012

No fault code found.

-------------------------------------------------------------------------------
Address 56: Radio        Labels: 8J0-035-1xx-56.clb
   Part No SW: 8P0 035 186 S    HW: 8P0 035 186 S
   Component: R Concert2+     H03 0280  
   Revision: 00H03000    Serial number: AUZ1Z3K6021148
   Coding: 0310011
   Shop #: WSC 06314 000 00000
   VCID: 42DD4473C8894EEA09F-8016

No fault code found.

-------------------------------------------------------------------------------
Address 62: Door, Rear Left        Labels: 8P4-959-801.lbl
   Part No SW: 8P4 959 801 F    HW: 8P4 959 801 F
   Component: Tuer-SG         H04 0050  
   Coding: 0000144
   Shop #: WSC 06314 000 1012544
   VCID: 42DD4473C8894EEA09F-8016

No fault code found.

-------------------------------------------------------------------------------
Address 72: Door, Rear Right        Labels: 8P4-959-802.lbl
   Part No SW: 8P4 959 802 F    HW: 8P4 959 802 F
   Component: Tuer-SG         H04 0050  
   Coding: 0000144
   Shop #: WSC 06314 000 1012544
   VCID: 43D34177D79347E2029-8016

No fault code found.

End----(Elapsed Time: 01:04, VBatt start/end: 12.0V/12.0V. VIgn 0.0V)------

[Crasher]

So you have replaced relay 1 (100) with a new genuine 4H0 951 253 (644)?

[DrSkoff]

Yes, also 644 and 643 relays.

[Crasher]

And still no ECU comms?

[DrSkoff]

Nothing.
Tested fuse locations under bonnet, 13 ECU, 14 Engine Components, 15 Engine module, glow pulg, 21 Lambda probe, 22, clutch pedal switch, 23 engine relay components, 24 engine components. All show Zero voltage.
Dash fuses 1 Dignostics/ Engine, 2 ABS, 3 Heating, 19 Quattro, 40 Starter, 41 Rear wiper. All show Zero voltage.

[Crasher]

We have an almost identical 2010 Superb here with a similar issue although still running perfectly, it has the MIL on and reporting a terminal 30 error which you deal with by fitted a 644 relay to replace the 100. This worked for a few minutes but came back. I followed the wiring from fuse box to ECU plug and it was perfect, then I noticed the harness was full of water and so was the back of the ECU plug... new ECU required but obsolete! Yours MAY still be available 03L 906 022 RB at £1610.40 , second hand one coming tomorrow to check it clears the code and then try and match it to the car. Check dash side fuse 2 has ignition live and the engine bay fuse 13 also ignition live plus engine bay fuse 10 permanent live. If these are OK you need to access the ECU and cut off its chastity belt to start probing with a multimeter.

[DrSkoff]

Removed the fuse box, found a wire has rubbed on the battery tray and corroded through. Stripped the wiring loom insulation and it appears there is only 1 wire affected. Bits ordered, hopefull have it fixed by the end of the week.