Code 8039: Filler flap actuating element

[mxt_77]

So, I'm getting the code in the title, but the problem isn't with the actuator itself.  Can anyone help me troubleshoot it further?

 

Vehicle:

* 2008 Carrera S

 

Symptoms:

* Durametric code 8039: "Filler flap actuating element" under Vehicle Electrical System.

 

Completed troubleshooting steps:

* Confirmed that the actuator does not move when locking/unlocking car using the remote.

* Clear the code, and it comes back the next time I lock/unlock the car using the remote.

* Removed the actuator, connected to 9v battery and confirmed that it would move in both directions (based on polarity).

* Ensured that the actuator was installed correctly and that the rod could move in/out freely.

* Used an ammeter and found resistance when checking the connector that plugs into the actuator.  Does this indicate a short?

* Performed a visual inspection of the connector and wiring inside the fender and frunk area and saw no problems.

 

I'd like to determine if there is a short in the wiring harness or if it is a problem with the associated Control Unit, so:

Questions:

* Which control unit does the Filler Flap Lock connect to?

* Where is this control unit located on an '08 Carrera S?

* What is the path of the wiring, once it passes the firewall?

 

Thanks for any help!

 

[Ahsai]

Unplug the actuator and check the connector side for VOLTAGE when you arm/unarm using the remote?

 

"*Used an ammeter and found resistance when checking the connector that plugs into the actuator.  Does this indicate a short?" Try not to do this again as this may damage the control unit (the multimeter is sending electricity to the control unit while measuring resistance).

[mxt_77]

Unplug the actuator and check the connector side for VOLTAGE when you arm/unarm using the remote?

I didn't specifically check w/ the voltmeter, but I'm going to say there was no voltage there.  If there had been, the actuator would've at least twitched when it was plugged in.

[jl-c]

Not necessarily, Porsche may use a pulse to close all the locking actuators. You wouldn't want volts on them all the time the car was locked would you, the battery would soon be flat? They would draw current continuously and in fact would probably burn out as their duty cycle is low. This is why after so many actuations the central locking stops and waits for so long before re-activating. (See you handbook for accurate figures, I forget!) They probably use a 0.5 to 1 second pulse, Then they just "sit" in the position they have moved to (or not in your case!)

Edited September 25, 2014 by jl-c

[mxt_77]

Sorry... I didn't mean to say that the actuator would twitch at the *moment* it was plugged in (i.e., during the process of plugging it in).  I meant to say that it would twitch when I hit the lock/unlock on the key fob while it was plugged in.

 

I assume the control module sends it +/-12V to actuate it.  I was successfully able to actuate it with a 9V battery for testing.  So, I know that the actuator is good, and since it didn't move while locking/unlocking the car, I can infer that there was no voltage at the connector.

 

 

Ultimately, I'd just like to find the actual control module.  Then, I can unplug the connector at both ends and use the ammeter to check for a short in the wire.  If none is found, then I'll know that it is the control module that has failed.  If one is found, then I'll have to decide if it's worth replacing the harness just to get the fuel filler door to lock again.  :(

Edited September 25, 2014 by mxt_77

[Ahsai]

http://www.renntech.org/forums/topic/38278-what-control-unit-is-under-drivers-seat-2005-997s/?p=202452

Hope someone will chime in with which wires are relevant.

[Loren]

So, I'm getting the code in the title, but the problem isn't with the actuator itself.  Can anyone help me troubleshoot it further?

 

Vehicle:

* 2008 Carrera S

 

Symptoms:

* Durametric code 8039: "Filler flap actuating element" under Vehicle Electrical System.

 

Completed troubleshooting steps:

* Confirmed that the actuator does not move when locking/unlocking car using the remote.

* Clear the code, and it comes back the next time I lock/unlock the car using the remote.

* Removed the actuator, connected to 9v battery and confirmed that it would move in both directions (based on polarity).

* Ensured that the actuator was installed correctly and that the rod could move in/out freely.

* Used an ammeter and found resistance when checking the connector that plugs into the actuator.  Does this indicate a short?

* Performed a visual inspection of the connector and wiring inside the fender and frunk area and saw no problems.

 

I'd like to determine if there is a short in the wiring harness or if it is a problem with the associated Control Unit, so:

Questions:

* Which control unit does the Filler Flap Lock connect to?

* Where is this control unit located on an '08 Carrera S?

* What is the path of the wiring, once it passes the firewall?

 

Thanks for any help!

 

Is there actually a something wrong with current operation of the car - or - is this just a Durametric code?

Sometimes there are bugs in the software is why I ask.

So, is there a problem in normal operation of the car?

[mxt_77]

Is there actually a something wrong with current operation of the car - or - is this just a Durametric code?

Sometimes there are bugs in the software is why I ask.

So, is there a problem in normal operation of the car?

 

Other than the filler flap not locking/unlocking, no.  There are no other problems with normal operation.  The doors lock/unlock as expected.

 

I'm not too worried about it, because I'm assuming it has been like that since I bought the car (used), and I just didn't notice it until I got the Durametric and stumbled across the code.  But, I'd hate to give some mischievous kid the opportunity to pour sugar in the tank, etc.  Although, nowadays, I'm guessing most people just assume the filler flap is locked and don't bother messing with it, unless they're willing to jimmy it open.

 

But, since I have been off work for the last week & a half, I thought I'd try sorting this issue out along with some of the other regularly scheduled maintenance that I've been doing.  I assumed it was just going to be a failed actuator, but unfortunately it looks like it wasn't that simple.

[Loren]

I guess you have inspected the actuator arm (part of item 10), guide rose (item 11), and the catch (item 7) that is on the door/flap?

 

(click to enlarge)

 

I know of at least one instance where we had a car that had the little catch on the door/flap missing -- they had also replaced the solenoid.

[mxt_77]

I guess you have inspected the actuator arm (part of item 10), guide rose (item 11), and the catch (item 7) that is on the door/flap?

 

Correct.  When I removed & reinstalled the actuator, I ensured that everything was in place and that the actuator arm could move freely, and that I could manually engage the lock properly.  But even when the actuator was not installed and was just plugged in to the connector (with no risk of interference or resistance), it still did not move when I locked/unlocked the car. 

 

At this point, I've ruled out everything but the wiring harness and control unit.  I highly doubt there is a problem with the wiring, though.  The TPMS sensor antenna comes through that same path and it has no issues.  I suspect it's going to come down to the control unit.  I'm just not sure if this is a software issue that can be resolved by re-programming or a hardware issue that will require a new part (and presumably programming, too).

 

I tried to see if I could reach the connector on the control unit referenced in the thread Ahsai linked too, but I couldn't get a good enough grip to disconnect it while contorted under the dash.  I might try again in the coming days when I have a chance.

[Loren]

Tank Cover ground = Brown/Brown wire

Tank Cover power (shared unswitched +12 volts) = Red/White and is fused at F6

 

(click to enlarge)

 

Check the fuse first (with an ohm meter out of the circuit).

If +12 VDC across the solenoid does not actuate it then it is either jammed in the mount or bad (even if new).

[mxt_77]

Thanks!