Lexus thermostat DTC
Some 2008-2009 Lexus vehicles equipped with the 2GR-FSE or 4GR-FSE engine may exhibit a MIL-on condition with DTCs P0128 (coolant thermostat below thermostat regulating temperature) and/or P0116 (engine coolant temperature range/performance problem).
This applies to 2008-2009 GS350, GS450H, IS250 and IS350 vehicles produced BEFORE the production change effective VINs as follows:
MODEL PLANT DRIVE PROD. CHANGE EFFECTIVE VIN
GS350 Tahara 2WD JTHBE96S*90045581
GS350 Tahara 4WD JTHCE96S*90023172
GS450h Tahara 2WD JTHBC96S*95019778
IS250 Tahara 4WD JTHCK262*95033047
IS250 Tahara 2WD JTHBK262*95099794
IS250 TMK 4WD JTHBK262*92094026
IS350 Tahara 2WD JTHBE262*95023043
IS350 TMK 2WD JTHBE262*92017385
REQUIRED TOOLS AND EQUIPMENT
TIS Techstream (software version 4.21.002 or later is required)
Super Long Life Coolant P/N 00272-SLLC2 (9.6 – 9.8 U.S. qts)
PREVIOUS P/N CURRENT P/N ITEM
16031-31020 SAME Water w/thermostat inlet sub-assembly
Using Techstream, check for any stored DTCs.
- If DTCs P0128 and/or P0116 are present, remove and inspect the thermostat housing and thermostat. If the thermostat assembly is securely seated in the thermostat housing, this TSB does not apply. Refer to the repair manual and follow diagnostics for the DTC(s). If the thermostat is not securely seated, refer to the repair manual for the specific vehicle for removal/installation of the thermostat assembly.
- Once the repair complete and verified, clear all DTCs.