SFI SYSTEM, Diagnostic DTC:P0117 and P0118

DTC Code DTC Name
P0117 Engine Coolant Temperature Circuit Low Input
P0118 Engine Coolant Temperature Circuit High Input

DESCRIPTION

A thermistor is built into the engine coolant temperature sensor and changes its resistance value according to the engine coolant temperature. The structure of the sensor and connection to the ECM are the same as that of the intake air temperature sensor.

Tip:

  • When the engine coolant temperature sensor output is outside the normal range, the ECM interprets this as a malfunction.

  • If DTC P0117 or P0118 is detected, the ECM performs engine control using an estimated engine coolant temperature calculated from the intake air temperature at the time of engine start and the intake air volume.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

P0117

Engine Coolant Temperature Circuit Low Input

Engine coolant temperature sensor output voltage is 0.05 V or less for 0.5 seconds (3 trip detection logic).

  • Open or short in engine coolant temperature sensor circuit

  • Short to power source circuit

  • Engine coolant temperature sensor

  • ECM

Comes on

DTC stored

P0118

Engine Coolant Temperature Circuit High Input

Engine coolant temperature sensor output voltage is 4.95 V or more for 0.5 seconds (3 trip detection logic).

  • Short in engine coolant temperature sensor circuit

  • Engine coolant temperature sensor

  • ECM

Comes on

DTC stored
Tip:

When any of these DTCs are output, check the engine coolant temperature using the GTS. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Coolant Temp.

Engine Coolant Temperature

Malfunction

-40°C (-40°F)

Open circuit

140°C (284°F)

Short circuit

WIRING DIAGRAM

A256089E99

CONFIRMATION DRIVING PATTERN

DTC P0117 and P0118 are detected when the engine idles for approximately 10 minutes.

CAUTION / NOTICE / HINT

Note:

After replacing the ECM, perform idle learning.

Click here

Tip:

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. READ VALUE USING GTS (COOLANT TEMP)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Coolant Temp.

      Powertrain > Engine and ECT > Data List

      Tester Display

      Coolant Temp

    5. Read the value displayed on the GTS.

      Standard Value

      Between 75 and 100°C (167 and 212°F) with warm engine.

      Result

      Result

      Proceed to

      -40°C (-40°F)

      A

      140°C (284°F)

      B

      Between 75 and 100°C (167 and 212°F)

      C
      Tip:

      • If there is an open circuit, the GTS indicates -40°C (-40°F).

      • If there is a short circuit, the GTS indicates 140°C (284°F).

    B

    READ VALUE USING GTS (CHECK FOR SHORT IN WIRE HARNESS)Click here

    C

    CHECK FOR INTERMITTENT PROBLEMS

    Click here

    A

  2. READ VALUE USING GTS (CHECK FOR OPEN IN WIRE HARNESS)

    1. Disconnect the engine coolant temperature sensor connector.

      A207455C48

      *1

      Engine Coolant Temperature Sensor

      *2

      ECM

      *a

      Front view of wire harness connector

      (to Engine Coolant Temperature Sensor)

      -

      -

    2. Connect terminals 1 and 2 of the engine coolant temperature sensor connector on the wire harness side.

    3. Connect the GTS to the DLC3.

    4. Turn the ignition switch to ON.

    5. Turn the GTS on.

    6. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Coolant Temp.

      Powertrain > Engine and ECT > Data List

      Tester Display

      Coolant Temp

    7. Read the value displayed on the GTS.

      Standard Value

      140°C (284°F)

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE ENGINE COOLANT TEMPERATURE SENSOR

    Click here

    NG

  3. CHECK HARNESS AND CONNECTOR (ENGINE COOLANT TEMPERATURE SENSOR - ECM)

    1. Disconnect the engine coolant temperature sensor connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      B17-2 - B31-95 (THW)

      Always

      Below 1 Ω

      B17-1 - B31-96 (ETHW)

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE ECM

    Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  4. READ VALUE USING GTS (CHECK FOR SHORT IN WIRE HARNESS)

    1. A255925C18

      *1

      Engine Coolant Temperature Sensor

      *2

      ECM

      Disconnect the engine coolant temperature sensor connector.

    2. Connect the GTS to the DLC3.

    3. Turn the ignition switch to ON.

    4. Turn the GTS on.

    5. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Coolant Temp.

      Powertrain > Engine and ECT > Data List

      Tester Display

      Coolant Temp

    6. Read the value displayed on the GTS.

      Standard Value

      -40°C (-40°F)

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE ENGINE COOLANT TEMPERATURE SENSOR

    Click here

    NG

  5. CHECK HARNESS AND CONNECTOR (ENGINE COOLANT TEMPERATURE SENSOR - ECM)

    1. Disconnect the engine coolant temperature sensor connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      B17-2 or B31-95 (THW) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE ECM

    Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR