Dtc 012 Overheating

Heater & Air Conditioning System. Lexus Is250, Is220D. Gse20 Ale20
Heater. Lexus Is250, Is220D. Gse20 Ale20

DESCRIPTION

INSPECTION PROCEDURE

CHECK FOR ENGINE COOLANT LEAKS

CHECK ENGINE COOLANT QUALITY

INSPECT THERMOSTAT

INSPECT WATER PUMP ASSEMBLY

DTC 012 Overheating

DTC 014 Difference Evaluation Overheating

DTC 017 Hardware Overheating


DESCRIPTION


DTC No.
DTC Detection Condition
Trouble Area
012
The surface sensor or control overheating sensor detects a temperature of 125°C (257°F) or more.
  1. Surface sensor (combustion heater assembly)
  2. Control overheating sensor (combustion heater assembly)
  3. Engine coolant circuit (for leaks, engine coolant quality, thermostat, water pump assembly)
014
When the engine coolant temperature is 80°C (176°F) and the combustion heater assembly is operating, the difference in temperatures detected by the surface sensor and control overheating sensor is 25°C (77°F) or more.
  1. Surface sensor (combustion heater assembly)
  2. Control overheating sensor (combustion heater assembly)
  3. Engine coolant circuit (for leaks, engine coolant quality, thermostat, water pump assembly)
017
When neither DTC 012 nor 014 is detected, the control overheating sensor or surface sensor detects a temperature of 130°C (266°F).
  1. Control overheating sensor (combustion heater assembly)
  2. Surface sensor (combustion heater assembly)
  3. Engine coolant circuit (for leaks, engine coolant quality, thermostat, water pump assembly)

INSPECTION PROCEDURE

1.CHECK FOR ENGINE COOLANT LEAKS

  1. Check for engine coolant leaks (Click here).



NG
REPAIR ENGINE COOLANT LEAKS
OK


2.CHECK ENGINE COOLANT QUALITY

  1. Check the engine coolant quality (Click here).



NG
REPLACE ENGINE COOLANT
OK


3.INSPECT THERMOSTAT

  1. Inspect the thermostat (Click here).



NG
REPLACE THERMOSTAT
OK


4.INSPECT WATER PUMP ASSEMBLY

  1. Inspect the water pump assembly (Click here).



NG
REPLACE WATER PUMP ASSEMBLY
OK

REPLACE COMBUSTION HEATER ASSEMBLY