Parasitic drain, but not typical.

[theDIYguy]

I have a 2013 ford fusion energi titanium with most of the extras, like keyless ignition, keyless entry, etc.  

 

Starting about a year ago my fuel filler door would randomly pop open.  So i replaced the button.  This seemed to help for a month or so.  Then it started doing it again.  Wasnt a big issue because its just the door.  So i didnt bother with the actuator or sensor during that time.

 

About 6 months passes with it randomly opening, then noticed it got worse.  Now it would pop open when the car was parked and off.  Seemingly on its own, as the modules were shutting down.  And once it pops, i closed it, without turning on car or opening the doors.  Only for it to pop on its own like 2 minutes later.  However due to this the low voltage battery began to drain while the car was parked.  Requiring a jump almost everytime.  Sometimes if the car hadn't sat long, i could start it but occasionally not all the modules would power up.  Like the radio and lcd stayed off a few times, sometimes it would say "key not detected" despite starting right up with a push of the button, meanwhile the same error message is shown on the instrument cluster.  

 

After getting forscan and running a few diagnostics and checking parts i determined the actuator works fine and the sensor is properly functioning, at the correct voltages.  Thus concluded the problem lies elsewhere.  However i cannot for the life of me find it. 

 

Now after so long and noticing patterns, ive learned more.  If i switch into or out of park on the gear shift, it immediately pops the fuel door.  And i was showing a low voltage error on the transmission control module and the pcm (which runs the fuel door button, sensor and actuator).   So i took the shifter apart and confirmed good connections between its sensors and no mechanical parts are touching or anywhere near the wire harness for the fuel door button, which is right next to the shifter.  The wire harness wraps around another direction, seemingly to avoid that problem. 

 

But now im stuck in the dark.  Everything seems to have good connections.  The car runs fine after a jump and the battery still holds a charge when tested out of the car.  The car shifts fine.  And im thinking the drain is caused by the "close fuel door" error shows on the instrument cluster, even after the car has been parked, powered off and locked up.  The fuel door will pop like 5 mins later and the error will show on the lcd of the instrument cluster, but wont turn off as long as the door is open.  If i close the door.  It turns off, but then then comes back on a few minutes later when the door inevitably pops again on its own. 

 

Im at my whitt's end with this thing.  Someone please help me.  Do i need to get the pcm changed?  Or is it the tcm?  Maybe just a bad connector in the engine bay?  Any suggestions will help.  Even if its just tests to run on forscan.  Hell i think i can stop the drain if i can turn off the "close fuel door" alert in the instrument cluster.  But i cant figure out how on forscan.  

[MeeLee]

I would start by looking at the fuse box. See if it's got any water in, bugs, dirt or grime.

 

Next, I would check the 12v battery voltage. Any readout below 11.7v and the battery needs replacing. A lot of electrical gremlins show up with just a low voltage battery.