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Discussion Starter #1
Last night the parking lights and instrument panel on my 2005 Caravan started flickering on and off while the headlight switch was in the off position. It happened with the car running, and also after I turned it off and locked it. As I was walking away, the lights were still flickering. I went back and played around with the headlight switch, and they finally stopped flickering. Would this be a switch problem, a relay problem, or a computer problem? I'm hoping just a switch. Thank you!
 

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Switch? That's a pretty good bet plus there's an extended lifetime warranty on them for the 2005 and 2006 model years.
 

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Discussion Starter #3
I read a lot of other posts while I was here, and noticed that several people had also mentioned bad battery connections, not related to parking lights like me, but other electrical issues. I checked, and mine were pretty grungy, so I cleaned them all up. Its hard to notice the dash lights during the day, but I'll watch tonight and see if it made a difference or not.
 

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Unless playing with the switch has a direct result in curing the problem, it could be more involved.
The parking/panel illumination lighting isn't hardwired to the headlight switch, but controlled by the BCM (body control module) and FCM (front control module) over the PCI (programmable communication interface) communication bus that carries messages between the modules.
The headlight switch sends a ~0.5v to 4.5v signal to the BCM depending what mode is selected. (If the headlight switch was ever unplugged and the BCM saw 0 volts on the lighting signal line, it would then turn the headlights on as a safety default).
The BCM then interprets what mode the driver selected and sends a command over the PCI bus to the instrument cluster for panel lights and how bright they should be.
It also sends a command over the bus to the FCM which is part of the IPM (integrated power module-the underhood fuse/relay box) to energize the parking light relay (that you will find inside the IPM) along with left and right side parking lamp fuses. Do the headlamps operate OK?
The only lights on the vehicle that are 'directly' controlled by a switch are the hazard lights and brake lights.
You might try swapping the parking light relay with a similar non-critical relay nearby. Corrosion can occur at the FCM terminal pins where they plug into the front of the IPM and underneath the IPM where the harness connectors plug in due to road and battery acid spray. The BCM usually stays nice and dry inside the vehicle. It can do intermittent things, but is fairly reliable.
The FCM and BCM can store fault codes and run tests that might help diagnose this, but would need an advanced scan tool (like the DRB III or equivalent), to do so. These diagram links below may differ slightly in wire color, etc., but are similar to the general layout found in your own vehicle.
A factory service manual with wiring diagrams and a voltmeter may be your best friend tor finding the culprit. It would probably have to act up for you in order to prove the faulty component. This is the stuff that makes 'intermittents' a challenge sometimes.
Parking lights: 2009-01-15_005253_dr_lighting.jpg
Instrument cluster illumination lights: Plymouth+Breeze+2000+Dash+Light+Wiring+Diagram.jpg
 

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Discussion Starter #6
My van is a base model with no automatic lights or upgraded options. The dash lights and parking lights are the only ones that seem to be involved. When they start to flicker on their own, it is usually right after I drive the car home and park it for the night. So far, if I cycle the headlight switch a few times they seem to turn off and stay off. They could be going on and off at other times and I wouldn't know it. I'm concerned that the lights could go on at night and run my battery down. Varkguy mentioned an extended lifetime warranty on a 2005-2006? Is there any way to see if this is the case? I would just run it over to the dealer if it was a warranty repair. Thank you for your help!
 
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