SFI SYSTEM(w/ Canister Pump Module), Diagnostic DTC:P012800

DTC Code DTC Name
P012800 Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)

DESCRIPTION

The ECM uses the engine coolant temperature sensor, installed to the water outlet, and the No. 2 engine coolant temperature sensor, installed to the radiator pipe assembly, to monitor the operation of the thermostat.

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory Note
P012800 Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)

Either of the following conditions is met (2 trip detection logic):


  • All of the following conditions are met for 5 seconds or more:


    1. The engine is started cold and then warmed up.

    2. When the estimated engine coolant temperature is 75°C (167°F) or higher, the actual engine coolant temperature is less than 75°C (167°F).

  • All of the following conditions are met for certain period of time:


    1. Cold start.

    2. The engine is running and the engine coolant temperature is increasing.

    3. The temperature detected by the No. 2 engine coolant temperature sensor is higher than the threshold temperature calculated based on the engine coolant temperature sensor value.

  • Water inlet with thermostat sub-assembly (thermostat)

  • Cooling system

  • Engine coolant temperature sensor

  • No. 2 engine coolant temperature sensor

  • Front exhaust pipe assembly

  • ECM

 Comes on DTC stored SAE Code: P0128

MONITOR DESCRIPTION



MONITOR STRATEGY

Frequency of Operation Once per driving cycle

CONFIRMATION DRIVING PATTERN

B004OX1E26

  1. Turn the power switch off and leave the vehicle for several hours.

  2. Connect the GTS to the DLC3.

  3. Turn the power switch on (IG) [A].

  4. Turn the GTS on.

  5. Enter the following menus: Powertrain / Engine / Data List / Coolant Temperature and Intake Air Temperature.

  6. Check that the value of the Data List item Coolant Temperature is 56°C (133°F) or less and the value of the Data List item Intake Air Temperature is between 0 and 35°C (32 and 95°F).

  7. Put the engine in Inspection Mode (Maintenance Mode).

    Click here

  8. Set the heater control to MAX HOT with fresh air mode selected and turn the A/C off.

  9. Start the engine.

  10. With the engine running, drive the vehicle at 80 km/h (50 mph) for 15 minutes [B].

    CAUTION:

    When performing the confirmation driving pattern, obey all speed limits and traffic laws.

    Tech Tips

    If the engine stops, further depress the accelerator pedal to restart the engine.

  11. After the value of the Data List item Coolant Temperature stabilizes, check that it is 75°C (167°F) or higher [C].

    Tech Tips

    If the value of the Data List item Coolant Temperature is less than 75°C (167°F) while driving the vehicle at 80 km/h (50 mph), inspect the cooling system and thermostat.

CAUTION / NOTICE / HINT

Tech Tips


  • When this DTC is output, check the engine coolant temperature using the GTS. Enter the following menus: Powertrain / Engine / Data List / Coolant Temperature. If the value of Coolant Temperature is lower than the actual engine coolant temperature, the engine coolant temperature sensor circuit may be malfunctioning. In this case, check the wire harnesses and connectors (and their connection condition) between the ECM and the engine coolant temperature sensor first.

  • Read freeze frame data using the GTS. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

PROCEDURE


  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P012800)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Engine / Trouble Codes.

    5. Read the DTCs.


      Powertrain > Engine > Trouble Codes
      Result
      Result Proceed to
      DTC P012800 is output A
      DTC P012800 and other DTCs are output B

      Tech Tips

      If any DTCs other than P012800 are output, troubleshoot those DTCs first.


    B

    GO TO DTC CHART Click here

    A

  2. CHECK COOLING SYSTEM


    1. Check for defects in the cooling system that might cause the system to be excessively cold, such as abnormal cooling fan operation or any modifications.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE COOLING SYSTEM

    OK

  3. INSPECT FRONT EXHAUST PIPE ASSEMBLY


    1. Inspect the front exhaust pipe assembly (exhaust flow control valve operation).

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FRONT EXHAUST PIPE ASSEMBLY Click here

    OK

  4. INSPECT WATER INLET WITH THERMOSTAT SUB-ASSEMBLY


    1. Inspect the water inlet with thermostat sub-assembly (thermostat opening temperature).

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE WATER INLET WITH THERMOSTAT SUB-ASSEMBLY Click here

    OK

  5. INSPECT ENGINE COOLANT TEMPERATURE SENSOR


    1. Inspect the engine coolant temperature sensor.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE ENGINE COOLANT TEMPERATURE SENSOR Click here Perform "Inspection After Repair" after replacing the engine coolant temperature sensor. Click here

    OK

  6. INSPECT NO. 2 ENGINE COOLANT TEMPERATURE SENSOR


    1. Inspect the No. 2 engine coolant temperature sensor.

      Click here

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE ECM Click here

    NG

    REPLACE NO. 2 ENGINE COOLANT TEMPERATURE SENSOR Click here