4 Lo / 4wd light randomly coming on??

The 4 low light and the green symbol that four-wheel drive is engaging has been coming on randomly. It just flashes but is not engaging. If I turn the truck off and back on it goes away. It's happened three times in the last week. Any ideas?

 

Likely either you have an actuator getting water in it or have one or more wires that are getting corroded or shorted.

First thing I'd recommend is checking the vent hoses on the actuators, if one is damaged or disconnected that actuator is almost certainly getting wanter and dirt in it.

https://www.tacomaworld.com/threads/4wd-system-operation-help-thread.742420/