Service four wheel drive light comes on and off for no reason.

Hello, Dave here, contributing to RepairPal and providing expert advice since 2010. You definitely need a technician to look at your vehicle to find out what is going on. If the one that has tested it can't find anything, it sounds like you need somebody else who has a little more knowledge and skill and proper equipment for testing. You could have any number of things occurring causing these problems. But one thing is for sure, it sounds like it's fairly consistently happening. As a result it should be easier to diagnose and determine what the failure is. Various sensors along with mechanical components are involved in these systems. So, it is impossible to guess what is happening. https://repairpal.com/auto-repair-near-me Click the link or call us at 877-913-1554. We'll gladly find you a certified RepairPal shop in your area.