Multiple electrical issues

Hello, when you say flasher, do you mean that your turn signals are not working at all on either side?

https://www.2carpros.com/articles/turn-signals-not-working-blinker

Okay, the Multiplex Control Module (Body Control Module) may be at fault here. It controls all the systems you're having trouble with. It actually controls almost everything in the van except critical engine functions. This Multiplex module can be scanned separately from the engine computer for diagnostic trouble codes. Alot of times with a module as complex as this one is, it can have different sections fail and others not effected. It also communicates with every other module in the van via a CAN Bus network.
It is also possible that there is more than one problem occurring but starting with having the Multiplex Module (MICU) scanned for diagnostic trouble codes is where you should start. These systems are too complex to guess if it's one thing or another, plus the cost of these modules can be a lot, so I recommend having it diagnosed correctly. If there is a loss of communication with part of the module and a section of the network is down, that can also cause these types of issues,

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

https://www.2carpros.com/articles/can-scan-controller-area-network-easy

https://www.2carpros.com/articles/how-to-replace-a-bcm-body-control-module

There are two of them, but they work together and are integrated with the front and rear Junction Boxes (Fuse/Relay panel), but you can't just replace it, they need to be programmed for the vehicle. You can check its connections for any water intrusion, but most likely the failure is internal. The first two diagrams are the front unit and the second two are the rear unit. These are considered to be Smart Fuse/Relay Junction Boxes since they have network communications running through them.
Check the exterior lamp assemblies for any water intrusion, if there's any moisture inside where the turn signal bulbs are. Any water intrusion can short out the bulb sockets and cause failures like this as well.