Lexus coolant codes
Some 2008-2009 Lexus vehicles equipped with the 2GR-FE or 4GR-FE engine may exhibit a MIL “ON” condition with one or both of the following codes:
P0128 (Coolant Thermostat belowThermostat Regulating Temperature)
P0116 (Engine Coolant Temperature Range/Performance Problem)
This TSB applies to vehicles produced before the Production Change Effective VINs shown below:
MODELÂ Â Â Â Â Â Â Â Â PLANTÂ Â Â Â Â Â Â Â Â Â DRIVETRAINÂ Â Â Â Â Â Â Â Â PROD. CHANGE EFF. VIN
GS 350         Tahara          2WD                        JTHBE96S*90045581
GS 350          Tahara         4WD                        JTHCE96S*90023172
GS450h         Tahara         2WD                        JTHBC96S*95019778
GS450h         Tahara         4WD                        JTHCK262*95033047
IS 250            Tahara         2WD                        JTHBK262*05099794
IS 250            Tahara         4WD                        JTHCK262*95033047
IS 250Â Â Â Â Â Â Â Â Â Â Â Â TMKÂ Â Â Â Â Â Â Â Â Â Â Â Â Â 4WDÂ Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â JTHCK262*92032298
IS 250Â Â Â Â Â Â Â Â Â Â Â Â TMKÂ Â Â Â Â Â Â Â Â Â Â Â Â Â 2WDÂ Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â JTHBK262*92094026
IS 350            Tahara         2WD                        JTHBE262*95023043
IS 350Â Â Â Â Â Â Â Â Â Â Â Â TMKÂ Â Â Â Â Â Â Â Â Â Â Â Â Â 2WDÂ Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â JTHBE262*92017385
REPAIR PROCEDURE
- 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 is not securely seated in the thermostat housing, replace the thermostat and the thermostat housing.