[ImperialCrown]

Welcome to Allpar. They flash once? Sounds like a security system or power sliding door/power liftgate or RKE lock/unlock actuation signal?
Any aftermarket alarm or remote start system?
It does sound like it is trying to tell you something. Many of these modules can store fault codes.

 

[thegeorgiaman]

It dosent have security. It does have electric doors and hatch. It usually happens 5 or 10 minits after parking. While I was changing oil yesterday I had to go to towne and get antifreese, gone about 30 min. when I got back the lights flashed once and no one was anywhere around the van. No doors had ben opend or anything. It hasent ran the battery down or caused any problems yet, but it is strange. Just trying to figure it out.

 

[MickM]

How old is the battery. Dieing batteries can cause some strange things to happen

 

[Doug D]

How old is the battery. Dieing batteries can cause some strange things to happen

+1! Even though the battery seem to be fine in my '06 Ram, I replaced it recently. Seven years is a long time for a battery (truck was built in Nov 2005). In our previous 2000 T&C Ltd, it would act odd at times when the battery started getting weak - never had a battery last longer than 45 months in that van.

 

[TWX]

It's also possible that the dealership had some odd inventory control security system in the van that could be converted to a personal van security system that they either disabled or else removed the bulk of when they sold it, if the original buyer didn't opt for that dealer-installed option, and now whatever hooks were there have started to malfunction.

Hopefully not, though, as that would be a PITA to find and diagnose.

 

[ImperialCrown]

With many pre-owned vehicles, it's hard to know what a previous owner has done. A peek under the driver's side dash may reveal added wiring and a black, plastic module for an aftermarket security system. Mopar offered the EVS 1 and EVS 2 that were often dealer installed and configurable to what features you wanted.
An intermittently contacting RKE button in the vicinity of the van may also flash the lights and up close you may hear the locks cycle as well.