I have a 2006 F-150 Super crew XLT 4X4 with the 5.4

Last Thursday the truck was parked in my yard and all the lights came on (interior and exterior) and the radio. the key was inside the house and the truck was locked.

I may have to call the truck Christine after this

It seems that without the key in the ignition it's acting like it's in accessory mode. When the key is used the starter won't turn.

I've disconnected the battery and have been working on checking a few items without success. At first I suspected a faulty ignition switch so I disconnected all the connections at the switch and when the battery is reconnected its the same.

A fellow at the parts store recommended to look at the under hood fuse box as they sometimes develop green disease due to moisture infiltration. Or maybe its the PCM (gawd)

Any suggestions would be greatly appreciated.

 

Was it raining during or shortly before the initial episode. Melting snow also counts, just in case.

It's extremely unlikely to be the PCM, it's going to be something far more mundane.

 

Yes its been raining intermittently for the past two weeks, really damp with about 10 deg C swings

 

Check for a leaky windshield.

 

Check your battery also, a weak battery can cause all sorts of weird electrical gremlins.

 

I'm planning on getting on this problem this weekend, thanks for the input

 

so far I have found the connector behind the drivers side kick panel to have lots of green corrosion on the lower terminals. There is no sign of water, but of course I live in a winter climate so I'm sure that moisture does exist behind the panel at least four months of the year.

 

Well the connector with the corrosion isn't the problem. I've isolated the circuits involved to be the connected to the lighting. With the fuses pulled the truck operates and starts normally, just no lights.... the search continues.

 

check for a bad relay sticking on??? just an idea.

 

I now have everything back in with the exception of the DRL Relays. The truck functions almost normally...lights operate manually but the interior dome lights are a little wonky. I'm still hunting for the problem but at least now I can use the truck if need be, once I reinstall the interior that is.

 

Engtek --
I know this post was 2 yrs ago but my 2006 F150 Supercab XLT gave me same symptoms when I started it the other day. Both flashers/Hibeam dash indicator lights on steady, shifter locked and won't budge. What I tried was as I switched the AC/heater to Off the lights went away and car drives/operates normally. When I'm driving if I place the AC back on either clockwise or counterclockwise Both flashers/Hibeam dash indicator lights come back on and the radio head/clock goes out.

Any help as to where to find this short? It was raining for 2 weeks in my area before we got back from vacation and I drove it.

Thanks!

 

You do not have a "short", you probably have a a bad ground due to corrosion. Pull the kick panels and inspect the grounds.

 

Were you able to solve your problem. my 2006 F150 has the same issue you described. I only able to shift out of park if the heater with is in the off position.when the heater swaths on both flashers and high beam lights are on steadily and the shift is locked in park

 

Read and follow post #12.

 

Here's a quick video to show you where the wires are and how to permanently fix the issue.