[johnboy1313]

The main wire that runs from the alternator connects to a black plastic relay box on the passengers strut tower. A second wire connects from that box to the battery. Theoretically, if the wire from the alternator were loose at the black plastic relay box, it would probably act as you describe.

 

[johnboy1313]

Also, the ELD unit shares a ground with several other components just in front of the cruise control box at the passenger's inner fender. Try taking that ground junction apart, cleaning it, and putting it all back together. It's just a bolt with a number of ring connectors on it. By chance does your window washer pump work when the alternator ISN'T charging? It shares the ground point.

 

[johnboy1313]

Also, check fuse 41 in that black plastic relay box to see if it is loose or corroded. It serves as the connection between the alternator and the battery.

 

[johnboy1313]

Today I was monitoring the Alternator Control Signal (ALTC), WHT/GRN wire on the alternator plug. When the alternator drops off and the lights are flashing, this voltage goes from the normal 2.3 volts to zero. Not sure if this could be a cause or simply the effect of the alternator output going to 12 volts.

According to the service manual, the ALTC wire should be outputting approximately 8V when the engine is fully warmed up and running. I've attached a pic of the page from the manual.

 

[johnboy1313]

The windshield washer does work when the problem shows itself (previous question).

I'm just reading back through the first parts of this thread and I wonder if we're barking up the wrong tree here. After the answers in the first couple of posts I no longer suspected the alternator. I'm looking closer at the lights that are coming on and what isn't working. You say all four door lights come on and the windshield washers don't work. Sometimes you have to look at the simple things that aren't working. Looking at the windshield washer circuit it is pretty simple...no PCM control. It is powered by a fuse in the under dash fuse box and controlled by a module, also in the fuse box. Additionally, the door open lights are also run by a module in the under dash fuse box.

Have you looked at the under-dash fuse box? I'd pull it loose and look on the back side for any signs of water intrusion. Water intrusion and it's subsequent corrosion, will do strange things and could be causing all of this.

He said the washer pump IS working.