If the reading is within the standard, but the problem still exists, replace the ECU (see ECU Removal/Installation in the Fuel System (DFI) chapter).
Water Temperature Sensor Circuit

1. ECU
2. Water Temperature Sensor
Water Temperature Sensor Output Voltage InspectionDFI Power Source
ECU Fuse Removal
Refer to the 30 A Main/15 A ECU Fuse Removal in the
Electrical System chapter.
ECU Fuse Installation
If a fuse fails during operation, inspect the DFI system to
determine the cause, and then replace it with a new fuse
of proper amperage.
Refer to the Fuse Installation in ...
KIBS Hydraulic Unit Communication Error (Service Code 1b, KIBS Equipped
Models)
KIBS Hydraulic Unit Communication Line Inspection
When the data (for status of KIBS hydraulic unit) is not
sent from the KIBS hydraulic unit to the meter unit and
ECU, the service code 1b is displayed.
The data is sent through the CAN communication line.
The service code 1b is detected with the ...
Idle Speed Control Valve Actuator Resistance Inspection
Turn the ignition switch to OFF.
Remove the air cleaner housing (see Air Cleaner Housing
Removal in the Fuel System (DFI) chapter).
Disconnect the idle speed control valve actuator connector
[A].
Connect a digital meter to the idle speed control valve
actuator connector [A]
...