No engine start - U01400 fault

[gonze]

Hi I am looking for some guidance with VCDS.

I removed and reinstated the injectors on my caravelle, have primed the low and high pressure fuel system. I have loosened the injector fuel pipe and it pumps when the ignition is turned so guessing I do not still have air in the system. The van cranks like it wants to start but unfortunately does not start.

I have scanned using an OBDeleven multi scanner and only have one fault: U01400 - no communications with body control module.

Would this stop the van from starting? From searching extensively on the forum and online this fault doesn’t seem to stop the vehicles starting. Additionally I can not hear the injectors clicking, what do I need to select within VCDS to try a resolve the issue.

I have done a continuity test on the LIN cable from the alternator to the battery negative terminal and I have continuity

 

[gonze]

Will VCDS show if the injectors are receiving a signal whilst the engine is cranking?

 

[bluezie]

If you just removed the injectors, the engine should self prime and start within a few seconds of cranking.
Why were the injectors removed, and were they stripped down?
Are you 100% certain all electrical plugs that were removed, are definitely fully connected again?

 

[gonze]

The injectors where removed as part of a rebuild following the EGR failing. The injectors where sent away for testing and all passed. I have double/triple checked every plug as hoped it was simply a loose plug

I inspected the LIN cable from the alternator plug to where the cable disappears by the gearbox and could find no visible damage or corrosion. With the ignition off the LIN cable gave me 11.4v to ground at alternator plug. With ignition on I only get 9.1v. I have installed a new 95ah Varta battery and programmed to van, I have now put this on charge just to rule low voltage from battery out.

I have not been able to find an article online stating engine no engine start with just the U014000 fault. I'm puzzled as the injectors are not operating.

Thanks for the reply.

 

[mmi]

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Will VCDS show if the injectors are receiving a signal whilst the engine is cranking?

Almost, VCDS can tell whether the ECU fires the injectors or not.

See for more details here:

Won’t start. No fault codes

Nice, if i disconnect camshaft sensor, engine will start so i quess camshaft module needs to be replaced. I couldn do it correctly. I have hex+can cable andwhile trying to "Tick "Group UDS requests" - by 7" it says i need new interface. So i got only 1 time logging whivh didnt show anything...

www.t6forum.com

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With the ignition off the LIN cable gave me 11.4v to ground at alternator plug. With ignition on I only get 9.1v.

It's a data bus thus measuring voltage on it is not very meaningful. The lower voltage just tells there is communication going on, or at least an attempt to.

 

[gonze]

Hi thank you for the response, I have scanned using VCDS and followed the other article to produce the attached data log files.

Today I tried the below without managing to get the engine to start;
- disconnected Cam sensor - made no difference although did show as a fault
- jump lead from the battery negative to engine block, in case of bad earth
- checked all fuses in engine bay, dashboard and under passenger seat.
- the high pressure fuel pump raises to circa 30k during cranking so assume this is not the issue

The faults shown:
- I have replaced the battery with a 95ah Varta and charged it overnight. Used VCDS to update the van, but still shows low voltage?
- The LIN fault I have continuity checked the alternator to battery and it’s ok. But from reading this fault should not stop the engine starting
- the 3x pump faults are due to no coolant in the system.

I’m stumped as to what to try next!

 

[mmi]

Please make a recording:

Tick the following in VCDS > Engine > Advanced Measuring Values,

IDE00021 Engine RPM
IDE00351 Main injection: start of activation
IDE00352 Main injection: duration of activation
IDE00407 Rail pressure regulation: status
IDE00589 Fuel pressure

Click Log - Start
Crank the engine - 5 seconds is enough.
Stop logging etc.
The logfile will be in folder C:\Ross-Tech\VCDS\Logs
Please post the logfile.

 

[gonze]

Apologies I meant to upload the below log

The third attempt detailed at the bottom of the log the engine has a rpm shown and an engine stat of start. Unfortunately it did not start !

 

[n10n]

Silly question I'm sure but were the injectors placed in to their original locations? They are individually adapted to ECU so changing cylinders could lead to wrong adaptations.

Lumpy T6 - Triggers Broom! Misfire & Vibration under 1500rpm.

Hi All, I have a 2018 T6, that I'm running out of patience with... and garages... So I have purchased VCDS to try and get to the bottom of it... First issue was it started to use coolant, I swapped a known good charge cooler to eliminate that, Max to min in around 100 miles, So took it to VW...

www.t6forum.com

As for the low voltage error, that is weird as the freeze frame clearly shows sufficient voltage. Maybe one of these (if your engine type has them) could give some more information:

IDE00018,Voltage terminal 15,12.284, V
IDE00019,Voltage terminal 30,12.141, V
IDE01834,Battery voltage,12.156, V
ENG130449-ENG130482,A flag to indicate the voltage vailidity-Bool type,Yes,
ENG113714-ENG99033,ESM_Battery_voltage-Voltage,12.13, V
ENG130446-ENG130481,Raw battery voltage reading-Voltage BIN7 V,12.1328, V
ENG130447-ENG130481,Scaled sensor value before validation for pbatt-Voltage BIN7 V,12.1094, V
ENG130448-ENG130481,Scaled sensor value before validation for vinj-Voltage BIN7 V,12.1328, V

Fault code 03022 - Local databus 4 apparently refers to LIN bus between alternator and battery management module, could be the reason for the voltage fault code.

 

[gonze]

Hi, I checked the injector serial numbers against the cylinder numbers with my scanner and all where in the original locations.

After a battery change is there a way to make the vehicle check the battery state or a adaptation to be deleted/relearned?

 

[mmi]

The third attempt detailed at the bottom of the log the engine has a rpm shown and an engine stat of start. Unfortunately it did not start !

Must assume that the air filter box is not in place as no indicated airflow during cranking.
Anyways, ECU seems (to try) to fire the injectors as "Main injection: duration of activation" is active. Also fuel pressure seems to be fine.

 

[mmi]

After a battery change is there a way to make the vehicle check the battery state or a adaptation to be deleted/relearned?

Upgrading Starter Battery - how to guide

My van (April 2017 T28) is fitted with a Moll battery. I am experiencing some issues with it not starting after a few days sitting on the drive. Now this could be due to the tracker I have fitted draining it but I doubt it, I'll do some drain current tests before taking the plunge. If I were to...

www.t6forum.com

 

[gonze]

At least it’s good news that the injectors are firing. The air box is installed with the two sensors plugged in. Could a lack of airflow reading stop it starting?

The only sensor not plugged in is the coolant header tank sensor, due to no water in the system. The charge cooler sensors are plugged in but the inlet and outlet pipes are loose due to accessing the cam sensor.

Also today I checked the cam and HPFP timing and both where correct

 

[gonze]

Upgrading Starter Battery - how to guide

My van (April 2017 T28) is fitted with a Moll battery. I am experiencing some issues with it not starting after a few days sitting on the drive. Now this could be due to the tracker I have fitted draining it but I doubt it, I'll do some drain current tests before taking the plunge. If I were to...

www.t6forum.com

Thank you, I used this post this morning to add the new battery but the low voltage fault remained

 

[n10n]

Maybe unplug the 2-wire connector to the shunt in battery negative, clear the ECU faults and see if anything changes wrt the low voltage fault?

Anyway most likely that's not the reason for the non-start.

 

[gonze]

From reading the article with the faulty crank sensor. If my engine is not starting is there a way to tell if either the cam or crank sensors are at fault?

One of my log files details the crank speed although only around 300rpm whilst cranking.

I tried today starting without the battery two wire plug connected but made no difference but also when scanned didn’t show as a fault whilst disconnected

 

[mmi]

At least it’s good news that the injectors are firing. The air box is installed with the two sensors plugged in. Could a lack of airflow reading stop it starting?

Missing airflow sensor reading would not prevent engine starting. But missing airflow certainly would. Of course you can experiment having no air hoses connected.

One of my log files details the crank speed although only around 300rpm whilst cranking.

That's normal cranking speed and the engine normally starts well below 200 rpm. See below: ECU fired the injectors at 169 RPM and engine immediately (within a fraction of second) starts (RPM jumps high up).

From reading the article with the faulty crank sensor. If my engine is not starting is there a way to tell if either the cam or crank sensors are at fault?

We can only hope the ECU would report if a sensor data would be too bad. By seeing the RPM reading I would expect the sensor be "good enough" to start the engine - as the ECU commands injectors to fire.

I have been told that (these Delphi) injectors can be tricky get back on working (actually injecting fuel) after being removed.
Can you smell diesel at the exhaust when cranked?
Does the engine "run" with diesel starting fluid sprayed into air intake?

 

[gonze]

I will buy some starter fluid today and give it a try. I haven’t noticed a diesel smell at the back of the van, I will smell the exhaust today after cranking.

From reading i have noticed a number of people having to +/- the timing slightly to get the engine to fire after a cam belt change. Is there a way to rule out needing to do this?

 

[gonze]

I tried easy start today and the van would run momentarily. So we went through the fuel system the flow and return to the HPFP had pressurised fuel inside. The injector return has fuel inside but the fuel rail is dry.

We primed the pump multiple times and then cranked the engine most times a small drip of fuel would come out of the injector high pressure pipe. On one occasion managed to get fuel to fire over the engine as though it had some substantial pressure.

The only fault that appeared was; P009000 - Fuel Pressure Regulator 'A' Control Circuit/Open. But this was only on two occasions. I have checked the various fuel circuit fuses and all found ok.

Something appears to be stopping the HPFP from sending fuel to the rail.

 

[n10n]

Looking at your log we have ’regulated operation via quantity control valve’ for IDE00416:



Looking at other logs in the forum I found a different one where IDE00416 says ’regulated oper. via press. control valve and quant. control valve’:

Won’t start [Resolved]

T6 204 diesel. Van was used on a long drive and then a trip to the shops. It was left 5 mins and then wouldn’t start. Turns over but doesn’t fire. no fault codes. There was a slight burning smell when I parked up and it looks as if the front egr pipe has a crack, rear one has already been...

www.t6forum.com

Could be just a coincidence or difference in VCDS version but now that you mentioned fault codes relating to pressure control valve I’m wondering if 1+1 could be two?

Just speculation but maybe van indeed notices that pressure control valve does not respond and tries to provide fuel with quantity control valve only. And maybe using quantity control valve only might allow to keep engine running once started.