I have a 1998 Town and Country with 266K Miles.

Just this week the Interior and Exterior Lights have begun to flicker on and off after the vehicle is shut off, with the lights off and the key out of the ignition.

I can hear the relays in the Fuse Panel under the hood clicking on and off.

I switched the relays and it still does it.
The only way I have found to make it stop was to pull the relays.
Checked all fuses in the panel under the hood and they are good.

So I thought maybe it was a bad Headlamp switch module so I bought one from Rock Auto and replaced it.
As you can guess I still have the problem.

I did note, that if the Head Lights are on while it is running everything is fine.

But if if I don't have the headlights on, no lights or just running lights they flicker and so do the interior lights.

Any ideas are welcome.

A little confused right now.

 

All of that is controlled by the BCM and some other modules and switches under the dash. The stuff under the hood is just the main wiring loom, ECM, TCM, and your engine components and sensors.

I don't think any of those except maybe ECM or TCM shorting can cause this. Probably not even those since the body controllers have their own 12V supplies and ALL wiring goes out from those. Chilton and Hayes manuals have complete wiring diagrams.

Relays wouldn't cause it since they just control large voltage with small voltage, and the things under the dash actually close the circuits they all use..

 

Well that's an odd one. Usually the 4th generation vans (2001-2007) get this affliction. The Body Control Module (BCM) located on the back of the interior fuse panel under the dash controls all of your lighting except for the high beam headlights. If the headlights don't flicker with high beams selected that's one indication you may have a BCM on the fritz. If they keep flickering you likely have a grounding issue somewhere. If you want diagrams send me a private message with an email address to send them to.

Is it a random or cyclic flicker?

 

The flickering is totally Random.

The only time it stops is if the vehicle is running and I have the headlights turned on.
Not sure if I get flickering with just the running lights and the vehicle running.

Wiring Diagrams would be great I will send you a PM.

Was told to look for broken wires/corrosion underneath the underhood fuze pannel and around the one under the dash.

Going to do that tonight.

 

Sent interior lighting/exterior lighting/headlight diagrams. Let me know if you need more.

 

First off the flickering is totally random.

If the headlamp switch is off, the parking/running lights, interior lights and low beam headlights all flash in unison randomly.
It doesn't matter if the van is running or not.

If I put the switch in the parking/running lamp position the only thing that flashes is the low beam headlamps.
Again it doesn't matter if the van is running or not.

Finally if the headlamp switch is on, there is no flashing at all.

If I shut the van off, pull the key and close the door.
After 3 minutes the lights all turn off, "Battery Saver" and there is no flashing of any lights.

So tonight, we have it sitting there that way with the lights on, they timed out after three minutes.
I am going to see what happens in the morning, hopefully the battery is not dead.

I have the wiring diagrams, any idea what part of the circuit I should look at?

I poked around under the hood and under the fusebox didn't find anything. I also looked all around the under the dash fuse box and didn't find anything either.

 

Boy I sure would've liked to have known how this one turned out!
Oh well...

 

I'm still not getting past flickering with the engine off. That's a new one. The CCD data bus and it's BCM is still powered with the engine off and keys in your pocket. It almost has to be related to the BCM or some input to it. It appears a load (headlights) kills the flickering which steers me back to a corroded connection somewhere but where. Might try getting the lights to flicker then pull fuses to see if you can get the flicker to stop. Whatever fuse kills the flicker may be the path to follow. Other than that try a wiggle check on any wire harness you can access and see if the flicker changes or stops.

"If I put the switch in the parking/running lamp position the only thing that flashes is the low beam headlamps." Low beams shouldn't be powered with switch in park lights. Many have complained of the headlight switch causing random loss of headlights, not so much flickering. Still you might try either changing the switch or disassembling and cleaning it. It gets gummed up with plastic and metal flakes in the grease. Many have had success by just cleaning the gunk out and relubing.

 

Simply stated the van is on its final resting place at the junk yard. I did try changing the switch it made no difference. So if anybody wants one I've got one to sell. There were other issues with the van that caused us to junk it. Major driveline vibratio which I think was coming from the differential.