A3 tdi No start issue. 2004 2.0

[DOUGLAS CLARKE]

Hi everyone,
If anyone has any ideas, any advice would be most welcome. The car is a 2004 140hp. The problems began with difficult starting, ie, cranking much longer than normal before starting for a few days, then a final failure to start at all. Rac guy said he could see no output from the ecu, and just wanted to tow to the garage. They did a few checks, and had no audi diagnostic equipment so were not able to diagnose the problem. In tank pump does not run with ignition on, but does run if I connect power directly to it. The car still will not start with the pump running. Fuel flows freely after the fuel filter. The tacho shows no sign of life whilst the engine is cranking, so maybe a crank sensor? Or maybe like the Rac guy suggested, a problem withthe ecu?
Any ideas or suggestions of what to check next?

 

[LEE69]

If it's turning over too slow you won't get a spark either. Replaced my starter motor and starts the first turn now

 

[DOUGLAS CLARKE]

It cranks over at normal speed, i.e. fast. Fitted a new battery, as the old one was struggling after a failed start attempt.
I also filled the tank as I've had problems in the past with other cars where low fuel level caused problems. No help in this case.

 

[NHN]

Does the Speedo light up in ignition turn?

 

[Bloxham]

You need to scan it with VCDS - no point in guessing or blasting it with the parts cannon

 

[DOUGLAS CLARKE]

Hi NHN, Yes, Speedo lights up with ignition on. What does this indicate?

 

[DOUGLAS CLARKE]

You need to scan it with VCDS - no point in guessing or blasting it with the parts cannon

I know that would be ideal, but I don't have vcds, and just hoped there would be some indicators to the problem I would be able to see without vcds first. I can operate a multimeter, and thought I would test the values from the crank sensor first, rather than replace it, etc.

 

[NHN]

Coolant sensors on these affect this too, but again you need diagnostic tools to help this, as you're just ******* in the wind tbh fitting parts etc without a direction to go.

Common issues, battery, starter, coolant sender, ignition switch but it's turning over so not this, starter relay, fuses, not all relevant to your issue.

 

[DOUGLAS CLARKE]

NHN, Do you know if the in tank pump should operate when ignition is turned on with these cars? Also, where is the relay I need to be testing? I assume the fuel pump relay. I have checked fuses.
Also, I have seen a diagnostic lead for sale from a company called www.totalcardiagnostics.com . This looks like a rip off of the vcds software and lead, would this be of any help to me, in your opinion?

 

[NHN]

When ignition is turned, the lift pump under rear seat pressures the fuel supply, lift the seat & listen for this, assuming you've checked fuel supply to the fuel filter already?

 

[DOUGLAS CLARKE]

Copied from my initial post; In tank pump does not run with ignition on, but does run if I connect power directly to it. The car still will not start with the pump running. Fuel flows freely after the fuel filter.

I haven't been able to check if the pump runs whilst cranking the engine yet, but if it should be operating whilst ignition is on, and isn't then I guess it isn't operating when cranking. Maybe this is pointing to fuel relay?

 

[NHN]

Check the relay hasn't come loose, mine did from factory, wasn't pushed home, so check relay for bad conduction, after a while the contacts become soiled so to speak, I just rub them back to bare metal with fine sandpaper.

The pump should always pressure the fuel on ignition, so if it's not running then this maybe related.

 

[DOUGLAS CLARKE]

Ok, from a quick Google, it looks like the fuel relay is inside the car, behind the panel just above the foot pedals.
I'll let you know how I get on.

 

[NHN]

That's exactly where it is yes, caused me no end of issues, until I realised it was that simple, that's not to say this is your issue, but if no pump then this is a place to start & the fuse.

 

[DOUGLAS CLARKE]

I've checked all the relays under the dash, all are working ok. Fuse is good too. There is no power getting to the pump with ignition on or when cranking. Does anyone know which relay specifically is the fuel pump relay so I can check there is power getting to the relay and check continuity of wiring to the pump.
This is a picture of my relays under the dash.

 

[ahtcap]

at a guess 449 relay

1. https://parts.vw.com/p/Volkswagen__/Relay-Rear/48118480/1K0951253.html

 

[DOUGLAS CLARKE]

Thanks for your help guys. I've just plugged in my newly acquired VCDS lead and the software says there is no communication from the engine control module. All the other control modules work ok. The RAC guy who originally recovered it said there was no communication from the ecu, so I think my ecu is faulty. I guess the best way forward is to send the ecu for test and repair. Is there any recommendations for who best to go to for this service in the UK?

 

[ch1z64]

Firstly why not copy and paste the coding thats already in the ecu back into the ecu as you have nothing to lose but a lot to gain if it fixes problem

 

[DOUGLAS CLARKE]

Firstly why not copy and paste the coding thats already in the ecu back into the ecu as you have nothing to lose but a lot to gain if it fixes problem

Ok, that sounds good. It's the first time I've used VCDS today, so not too familiar with everything. I'm sure it's easy, but where do I find the coding that's in the ecu to copy it, then where do I paste it? Would be great if it's still a potentially simple fix.

 

[ch1z64]

Ok, that sounds good. It's the first time I've used VCDS today, so not too familiar with everything. I'm sure it's easy, but where do I find the coding that's in the ecu to copy it, then where do I paste it? Would be great if it's still a potentially simple fix.

Go into your vcds ( fo auto scan first ) save it . Then find your ecu module and copy the long code in it the if i mind you should be able to paste underneath the long coding and hit do it and then if accepted it will say coding accepted . Come out off vcds and remove key ftom ignition thrn give it a cpl mins and go back in and autoscan again

 

[DOUGLAS CLARKE]

Go into your vcds ( fo auto scan first ) save it . Then find your ecu module and copy the long code in it the if i mind you should be able to paste underneath the long coding and hit do it and then if accepted it will say coding accepted . Come out off vcds and remove key ftom ignition thrn give it a cpl mins and go back in and autoscan again

I cant find any code for the ecm in the autoscan. I have included a copy of the scan here in the hope someone can offer any further advice.
Is there a relay for the engine control module, if so, does any one know where it is on the A3? I have accessed the ecm to check the multiplug but all seems ok there. I haven't checked for power to the ecm as I don't know which wires to check.


Tuesday,19,May,2020,15:36:45:39370
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64
VCDS Version: 18.9.0.2
Data version: 20180927 DS296.0
www.Ross-Tech.com

VIN: WAUZZZ8P15A082208 License Plate: KR54NLC
Mileage: 302440km-187927mi Repair Order:

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

Chassis Type: 8P (8L - Audi A3/S3 (1997 > 2005))
Scan: 01 02 03 08 15 16 17 22 35 37 45 55 56 57 75 76

VIN: WAUZZZ8P15A082208 Mileage: 302440km-187927miles
-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 1K0-907-379-MK60-F.lbl
Part No: 1K0 907 379 K
Component: ESP FRONT MK60 0104
Coding: 0023174
Shop #: WSC 06435 000 00000
VCID: 3A7B0B1875C6539ADB-806E
2 Faults Found:
01314 - Engine Control Module
013 - Check DTC Memory - Intermittent
01314 - Engine Control Module
004 - No Signal/Communication
-------------------------------------------------------------------------------
Address 08: Auto HVAC Labels: 8P0-820-043.lbl
Part No SW: 8P0 820 043 D HW: 8P0 820 043 D
Component: KlimavollautomatH13 0150
Revision: 115714 Serial number: 8P0820043D
Shop #: WSC 06314 000 00000
VCID: 2D513044B488F4224E-8078
2 Faults Found:
00483 - Control Module for Auxiliary Air Heater
013 - Check DTC Memory
Freeze Frame:
Fault Status: 01101101
Fault Priority: 3
Fault Frequency: 1
Reset counter: 233
Mileage: 302442 km
Time Indication: 0
Date: 2020.04.14
Time: 00:03:29
Freeze Frame:
ON
01206 - Signal for Duration of Ignition Off Time
008 - Implausible Signal
Freeze Frame:
Fault Status: 01101000
Fault Priority: 3
Fault Frequency: 1
Reset counter: 233
Mileage: 302442 km
Time Indication: 0
Date: 2020.04.14
Time: 00:03:29
Freeze Frame:

-------------------------------------------------------------------------------
Address 15: Airbags Labels: 8P0-959-655-84.lbl
Part No SW: 8P0 959 655 D HW: 8P0 959 655 D
Component: Airbag 8.4ED H00 0140
Coding: 0011603
Shop #: WSC 06314 000 00000
VCID: 438576FC020C125288-8016
No fault code found.
-------------------------------------------------------------------------------
Address 16: Steering wheel Labels: 1K0-953-549-MY8.lbl
Part No SW: 1K0 953 549 A HW: 1K0 953 549 A
Component: Lenksäulenmodul 012 0030
Coding: 0000012
Shop #: WSC 06314 000 00000
VCID: 306F2930A3BA99CA65-8064
No fault code found.
-------------------------------------------------------------------------------
Address 17: Instruments Labels: 8P0-920-xxx-17-MY7.lbl
Part No SW: 8P0 920 981 A HW: 8P0 920 981 A
Component: KOMBIINSTR. VDO H73 0300
Revision: D04 Serial number: 2249DD04000226
Coding: 0004413
Shop #: WSC 00444 210 87173
VCID: 36631F2841DEB7FA3F-8062
No fault code found.
-------------------------------------------------------------------------------
Address 56: Radio Labels: 8P0-035-1xx-56.lbl
Part No SW: 8P0 035 186 C HW: 8P0 035 186 C
Component: concert II EU H51 0100
Revision: 01S Serial number: AUZ2Z3D1628244
Coding: 0001001
Shop #: WSC 06314 000 00000
VCID: 326B2338ADB6ABDA13-8066
1 Fault Found:
00003 - Control Module
014 - Defective
Freeze Frame:
Fault Status: 01111110
Fault Priority: 5
Fault Frequency: 1
Reset counter: 255
Mileage: 302442 km
Time Indication: 0
Date: 2020.04.12
Time: 01:20:05
Freeze Frame:
Bin. Bits: 10000

End-------------------------(Elapsed Time: 04:10)--------------------------

 

[ch1z64]

This video might help from Roos tech about your code ()

 

[DOUGLAS CLARKE]

Ok, a little embarrassing, but I eventually got the car going! The car belongs to my son in law and he had a problem with the radio after a passenger spilled cider over the radio whilst trying to put it in the drink holder. This caused the radio to intermittently turn itself on, draining the battery overnight. Before he found out what the drain issue was, he messed about with the fuses under the bonnet in an attempt to locate the drain issue. He must of inadvertently removed a fuse supplying power to the ecu and replaced it in another previously empty spot. He then bought a new battery, which of course still failed to start the car.I only found out his fuse error in desperation, when I filled every blank fuse slot with a fuse. Hey presto, the VCDS was now communicating with the ecu and I could hear the pump working on ignition on. All I need to do now is find out which fuse is the one supplying the ecu power and make sure it's the correct amps. Thanks to everyone who tried to help with info.

 

[LEE69]

lol clip around the ear for that then
Glad it's running