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Discussion Starter · #1 ·
Hi, would appreciate some help with this one. Running fine until this morning when it refused to start.

Didn't hear the pump prime so started there -
  • RPM @ ~200 when cranking
  • 12v at fuses, 167 relay, and pump controller under rear bench
  • Jumping the relay doesn't run the pump
  • Pump runs fine with a direct 12v feed
Is the controller bad (can it be tested) or is there something else to look for?
Thanks.
 

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2001 Amulet Red 225 coupe.Owned from new as well as a Nurburg VXR & an XR3, all from new.
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Hi, If it's quattro is there more than 1/2 a tank of fuel, less than 1/2 tank can cause problems with jet pump if there are leaks in pump hoses.
Hoggy. :)
 

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2001 Amulet Red 225 coupe.Owned from new as well as a Nurburg VXR & an XR3, all from new.
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95,091 Posts
Hi, As usual a fault scan with a VAG specific scanner should help, otherwise just guessing.
Hoggy. :)
 

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Discussion Starter · #6 ·
Cheers Hoggy, appreciate the help.

Have an older VCDS cable that I don't think will work and OBD Eleven won't connect for some reason (hasn't for a while). Have ordered new cable/dongle.
 

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With the ignition off you should get 12v from Fuel Pump control module connector 1 and 6 (2 big terminal). With the ignition switch On you should get 12v from terminal 3 and terminal 6 (big terminal with 2 small terminal beside it) Make sure thr connector is disconnected from the FPCM.


Check the low pressure fuel sensor, it should be Part #. 06E 906 051 K
 

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2007 3.2 VR6 Roadster
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@ TTBar - As noted, a fault scan should help identify and narrow down the issue. To help understand what the DTC codes mean, you can run a Google search for "Ross Tech xxxxx" where xxxxx is the fault code. The search results will include a link to the Ross Tech Wiki for that specific DTC which includes possible symptoms, causes and solutions.
 

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Discussion Starter · #10 · (Edited)
Great, thanks for the tips.

I have 12v at terminals 1 and 6 at the controller and at 3 and 6 with ignition on.

Fault code P3045

The controller in there now is 3C0906093C but should this be 1K0906093J or are they the same? Assuming this has failed...
 

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It should be 3C0906093C (Blue) if your TT is Euro version. US version use Green.

Usually a faulty Fuel Pump Control Module will start the engine then stall after few seconds.

Are you using the updated version of Low Pressure Fuel Sensor? The older version could fail according to the TSB.
 

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You may have checked this but did you check the "undocumented" fuse in the trunk? By undocumented this fuse is not described in the owner's manual (in fact the entire trunk fuse box is not mentioned) but it is mentioned in the service manual. Just making sure you are aware of this.
 

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I forgot to mention, active and stored fault code can be very confusing when working with VAG vehicles. When the battery is connected, when electrical connector is disconnected for example Fuel pump control module, fault code will be saved and stored. Make sure not to confuse the stored fault as active. Always Erase and Rescan to prevent confusion.
 

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Discussion Starter · #14 · (Edited)
You may have checked this but did you check the "undocumented" fuse in the trunk? By undocumented this fuse is not described in the owner's manual (in fact the entire trunk fuse box is not mentioned) but it is mentioned in the service manual. Just making sure you are aware of this.
Hi, no, I didn't know this. Where can I find info on this? Thanks.

Edit: Fuse panel F "In luggage compartment, right rear -1-"? I have 12v at the controller though, so not sure if this is a problem.

Have a new controller ordered already...
 

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Discussion Starter · #16 ·
Ah, no, it would be great to find a blown fuse but I have 12v at terminal 1 in the connector. :)
Rectangle Slope Font Parallel Screenshot
 

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Discussion Starter · #17 ·
For the benefit of any Googlers, this is the pump controller 3C0906093C. It sits under the inspection panel above the lift pump under the rear seats.

Blue Azure Publication Book Font

It had some signs of overheating with an oily substance seeping out from the connector. There was also some evidence of heat damage on the blue casing.
Yellow Material property Rectangle Composite material Toy

I butchered it for a closer look and it appears that a transistor did overheat and fail.
Grey Ingredient Recipe Rectangle Automotive tire

Couldn't find one locally and I'm reluctant to pay double at the main dealer, so I ordered online from Trodo.


Winparts also has it around the same price.
 

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Oh yeah that thing was definitely melted down, lol. Looks like problem solved now then? :)
 
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