Toyota Tundra Service Manual > Touch Select 2-4 And High-low System: Four Wheel Drive (4WD) Low Switch Circuit Range / Performance (P2772)
DESCRIPTION When the transfer is switching between 4H and 4L, the H4 and L4 terminals of the transfer indicator switch are in one of the ON/OFF combinations listed in the table below. Terminal In 4H Switching between 4H and 4L In 4L H4 OFF (OPEN) ON (GND) ON (GND) L4 OFF (OPEN) OFF (OPEN) ON (GND) T ...