No Shift From 2H To 4H
WARNING: This page is about a different car, the 2002 Toyota Tundra and 2001 Toyota Tundra. However, it is still accessible from the selected car via links, so may be relevant.
Open 4WD fuse. Wiring harness open, shorted or pinched. Faulty touch select 2-4 switch. VSS inoperative or inaccurate. 4WD position switch inoperative or inaccurate. 4H indicator light circuit faulty. Transfer shift actuator malfunction. ADD control system faulty. 4WD control ECU malfunction. Transfer case mechanical malfunction.