Carista - prime a new fuel filter?

afaik - NO

you cant command/run the fuel lift pump/s from Carista,

you can with VCDS or other Diag Kit (Autel for example)
 
Does the lift pump operate with unlocking and opening the drivers door? Could this be used to prime the fuel system, it would probably take several goes?
 
Not T6 specific, but VAG so you get the idea . . . .




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I haven’t changed a T6 fuel filter yet but on others I’ve just filled the filter with a syringe before installing the hoses.
 
it looks like.


Primary pump is in the fuel tank . . . (feed unit)

supplementary pump is in engine bay next to fuel filter . .




J538 - Fuel Pump Control unit. ---> G6 PWM fuel pump
J623 - Engine control unit (controls fuel relays)

J17 - fuel pump relay in E-box ---> V393 supplementary fuel pump
J49 - Fuel pump realy2 - E-box

example in tank pump . . .

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example HPFP . . . .


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example v393 supplemental lift pump, (not for a T6 just to see what one looks like)


1608569172619.png
 
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You could introduce 12v to the pump supply cables in the connector block under the seat?
 
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You could introduce 12v to the pump supply cables in the connector block under the seat?
That’s the diagram I’ve been searching for for the last 30 min, I haven’t found it yet.
Seems like a cheap and easy solution.
 
Tank pump here:

G - fuel gauge sender
G6 - primary lift pump

J285 Control unit in dash panel insert


edit:*******************
J538 - petrol engines only
J538 Fuel pump control unit


********************************



T6b 6-pin connector, black, on fuel tank

T10c 10-pin connector, yellow, in E-box


colours:
Bl/ge = Blue/yellow
Br = Brown

*3 derv engine
*4 petrol engine

1608573594583.png
 
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Engine bay lift pump here:

J17 Fuel pump relay, in E-box in engine compartment
J49 Electric fuel pump 2 relay, in E-box in engine compartment
J519 Onboard supply control unit
J623 Engine/motor control unit, in E-box in engine compartment
T2dp 2-pin connector, black, near fuel filter
V393 Supplementary fuel pump
D110 - main relay +12v supply


1608573924425.png
 
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it doesn't look like the fuel pump wires goes via the seat base connection point?



1608574269907.png1608574278184.png1608574288411.png
 
I haven’t changed a T6 fuel filter yet but on others I’ve just filled the filter with a syringe before installing the hoses.
I just opened the drivers door and turned the key several times to prime the filter when I changed mine - and it started without hesitation.
 
I just opened the drivers door and turned the key several times to prime the filter when I changed mine - and it started without hesitation.
Worked for me 2nd time of trying. 1st time I was just turning the key on to off several times and it didn't start then I tried priming again but removed key each time and I'm sure I could hear the pump going on key out. Anyway it fired up on 2nd attempt. Phew! :)
 
No fuel pump prime on a T6 Diesel, (with door open or IGN on)

but there is on the Petrol TSI van. (the Pre-prime that is)

What you can hear is the Auxiliary coolant pump running - by all accounts.

you can drive the lift and secondary fuel pumps from VCDS - they have a different sound.
 
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Oh wow! Guess I was very lucky as I only have OBD11 so could have ended up stranded.
At least we now know it will prime eventually so long as your starter battery is good. :laugh:
 
I only have OBD11
OBDeleven can do that, too. Of course!
Engine > Output test > Fuel pump electronics​
Or​
Engine > Basic settings > Initial fuel filling.​
You'll definitely know when it works - very distictive sound. No harm experimenting :thumbsup:
 
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I just opened the drivers door and turned the key several times to prime the filter when I changed mine - and it started without hesitation.
So of I turn the ignition on and off a few times it will fill the fuel filter? In this case I should be able to take off the supply to the fuel filter and diesel should flow out the pipe when the key is turned? That doesn't happen in my case. Possibly a problem with the pump in the fuel tank?
 
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