COMBUSTION TYPE POWER HEATER SYSTEM, Diagnostic DTC:012,014 and 017

DTC Code DTC Name
012 Overheating
014 Difference Evaluation Overheating
017 Hardware Overheating

DESCRIPTION

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

012

Overheating

The surface sensor or control overheating sensor detects a temperature of 125°C (257°F) or higher.

  • Heater assembly (surface sensor)

  • Heater assembly (control overheating sensor)

  • Engine coolant circuit (leaks, engine coolant quality, thermostat, water pump assembly)

014

Difference Evaluation Overheating

When the engine coolant temperature is 80°C (176°F) and the heater assembly is operating, the difference in temperatures detected by the surface sensor and control overheating sensor is 25°C (77°F) or higher.

  • Heater assembly (surface sensor)

  • Heater assembly (control overheating sensor)

  • Engine coolant circuit (leaks, engine coolant quality, thermostat, water pump assembly)

017

Hardware Overheating

When neither DTC 012 nor 014 is detected, the control overheating sensor or surface sensor detects a temperature of 130°C (266°F).

  • Heater assembly (surface sensor)

  • Heater assembly (control overheating sensor)

  • Engine coolant circuit (leaks, engine coolant quality, thermostat, water pump assembly)

PROCEDURE

  1. CHECK FOR ENGINE COOLANT LEAKS

    1. Check for engine coolant leaks.

      for 1AD-FTV:

      Click here

      for 2AD-FHV:

      Click here

      for 2AD-CCo, 2AD-DPF:

      Click here

    Result

    Proceed to

    OK

    NG

    NG

    REPAIR ENGINE COOLANT LEAKS

    for 1AD-FTV:

    Click here

    for 2AD-FHV:

    Click here

    for 2AD-CCo, 2AD-DPF:

    Click here

    OK
  2. CHECK ENGINE COOLANT QUALITY

    1. Check the engine coolant quality.

      for 1AD-FTV:

      Click here

      for 2AD-FHV:

      Click here

      for 2AD-CCo, 2AD-DPF:

      Click here

    Result

    Proceed to

    OK

    NG

    NG

    REPLACE ENGINE COOLANT

    for 1AD-FTV:

    Click here

    for 2AD-FHV:

    Click here

    for 2AD-CCo, 2AD-DPF:

    Click here

    OK
  3. INSPECT THERMOSTAT

    1. Remove the thermostat.

      for 1AD-FTV:

      Click here

      for 2AD-FHV:

      Click here

      for 2AD-CCo, 2AD-DPF:

      Click here

    2. Inspect the thermostat.

      for 1AD-FTV

      Click here

      for 2AD-FHV:

      Click here

      for 2AD-CCo, 2AD-DPF:

      Click here

    Result

    Proceed to

    OK

    NG

    NG

    REPLACE THERMOSTAT

    for 1AD-FTV:

    Click here

    for 2AD-FHV:

    Click here

    for 2AD-CCo, 2AD-DPF:

    Click here

    OK
  4. INSPECT WATER PUMP ASSEMBLY

    1. Remove the water pump assembly.

      for 1AD-FTV: Click here

      Click here

      for 2AD-FHV: Click here

      Click here

      for 2AD-CCo, 2AD-DPF:

      Click here

    2. Inspect the water pump assembly.

      for 1AD-FTV:

      Click here

      for 2AD-FHV:

      Click here

      for 2AD-CCo, 2AD-DPF:

      Click here

    Result

    Proceed to

    OK

    NG

    OK

    REPLACE HEATER ASSEMBLY

    NG

    REPLACE WATER PUMP ASSEMBLY

    for 1AD-FTV:

    Click here

    for 2AD-FHV:

    Click here

    for 2AD-CCo, 2AD-DPF:

    Click here