2012 B7 Passat 3.6 with a weird issue

[VW_R36suit]

Hello guys.

Bought a new battery about 6 months ago. Didn't drive the car for 5 days and was on my way to work and it was flat. Got a jumo and few days later same.

One day I walk outside and I hear the priming noise before I evwn unlock the car. Pull the FP fuse and it stops. Just to be sure I changed it, with no change. So I drive around like normal stop the car and lock it. No priming sound. My best guess is the sound starts about 20 minutes after locking the car.

Some extra info.
Car locks perfectly.
All lights are off.
Fuel economy is good.
Power is factory standard.
Literally other than this it is fine.

If anyone has ever experienced this and has a fix I'd be super great full as currently I'm removing the fuse at night to avoid battery drain.

[MIG]

That's a pretty weird issue, what's the fuse number you are pulling?

I will check out the wiring diagrams tonight, but if I remember correctly, the BCM controls the fuel pump module under the rear seats.
I would be testing the input to the enable signal at the pump module and be seeing if the BCM is commanding the pump on.

[VW_R36suit]

I think fuse 27

[VW_R36suit]

That's a pretty weird issue, what's the fuse number you are pulling?

I will check out the wiring diagrams tonight, but if I remember correctly, the BCM controls the fuel pump module under the rear seats.
I would be testing the input to the enable signal at the pump module and be seeing if the BCM is commanding the pump on.

I think fuse 27? Was complicated reading it backwards as all the fuse diagrams where LHD.

I can run a test for errors as I have the OBD11

[MIG]

SC27 feeds the fuel pump module directly; that's the one under the back seats.

Here is the pinout of the module,

Pin 1 = Power in (SC27)
Pin 2 = ECU PWM
Pin 3 = Power in (SC10)
Pin 4 = Fuel gauge out
Pin 5 = Gnd (Control)
Pin 6 = Gnd (Pump)
Pin 7 = BCM pin T52b/38 pump enable
Pin 8 = Fuel gauge two out (AWD only)

I would check to see if a signal is present on pins 2 and 7 when the unit starts to prime itself.

[VW_R36suit]

SC27 feeds the fuel pump module directly; that's the one under the back seats.

Here is the pinout of the module,

Pin 1 = Power in (SC27)
Pin 2 = ECU PWM
Pin 3 = Power in (SC10)
Pin 4 = Fuel gauge out
Pin 5 = Gnd (Control)
Pin 6 = Gnd (Pump)
Pin 7 = BCM pin T52b/38 pump enable
Pin 8 = Fuel gauge two out (AWD only)

I would check to see if a signal is present on pins 2 and 7 when the unit starts to prime itself.

I have seen a few videos on YouTube of this module getting replaced.

What type of tools would you recommend?

Thanks super appreciate the help.

[MIG]

A cheap multimeter and some T-Pins to back probe the connector should be plenty to troubleshoot the issue.

Check out this YouTube channel; this guy goes over troubleshooting different modules etc
DiagnoseDan - YouTube

[VW_R36suit]

A cheap multimeter and some T-Pins to back probe the connector should be plenty to troubleshoot the issue.

Check out this YouTube channel; this guy goes over troubleshooting different modules etc
DiagnoseDan - YouTube

Really appreciate the help.

Will take me some time to gwt around to this, so hopefully next week. Have 2 children with car seats and best to start next week.

[VW_R36suit]

I checked the OBD11 scan for error ans got tbis

Fuel pump relay - open circuit/short circuit to ground?

[MIG]

Have you got the full scan results?

It's pointing to the most likely cause being the fuel pump module, but I would want to test it to be sure, don't want to throw the parts cannon at it