I have an apparent short in the Interior Light/Courtesy Light circuit of my 2000 Expedition Eddie Bauer. When the circuit is energized, after a very short time the interior and running board lights start flashing and you can hear the circuit breaker cycling repeatedly. Last time I drove it I didn't observe any problem. Vehicle sat for about a week and battery was low enough that the solenoid only clicked when I attempted to use it, and I first observed the apparent short symptoms. However, over the past few years I have observed that if a door or lift gate was left open for any length of time, the battery would appear to be partially drained.

I have not been able to locate an Expedition wiring schematic. Can anyone point me to a source, preferably on-line? Also does anyone have experience with Expedition wiring or this problem in particular, and can point me in the right direction to diagnose this? (I am somewhat familiar with Ford wiring and diagnosing problems as I worked as a Ford Service Zone Manager for a few years, but that was back in the early '80s).

Thanks much for any help or suggestions.

 

drivers door gets a lot of open / close cycles... I would look at the wire / flex point , where it comes out of the door and goes into the front door post.

 

You can "rent" online access to the shop manual + wiring manual + etc. everything for your vehicle year and model for $19.95 for a month of access at both Motorcraft.com (follow the tech resources path) or at Helminc.com (the official printer of the manuals, they have online access too).

 

It looks to me as if you have 2 maybe 3 issues at the same time.
1. The battery health seems questionable and may need replacement.
2. The breaker cycling is current right at the level it will still try to reset itself quickly. Could be a bulb filament 'partially' shorted.
3. Alternator may have a faulty diode stack that is draining the battery when setting but will still charge the battery when engine is running.
I would address the battery first, the alternator to see if it has the fault, then the ckt breaker issue.
Good luck.
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