ECD SYSTEM, Diagnostic DTC:P1608

DTC Code DTC Name
P1608 Open, Short to B+ or Short to GND in Coolant Temperature Lamp Circuit

DESCRIPTION

When engine coolant temperature is more than 118°C (244.4°F), the water temperature warning light comes on.

DTC No. DTC Detection Condition Trouble Area Possible to Detect
Ignition Switch Engine Run
P1608 Open or short in water temperature warning light circuit.

  • Water temperature warning light circuit

 ON ON

FAIL-SAFE

DTC No. Fail-safe Operation Fail-safe Deactivation Condition
P1608 - -

WIRING DIAGRAM

A0136GXE02

INSPECTION PROCEDURE

Tech Tips


  • If the ECM is replaced, variant coding (variant coding indicates the presence of vehicle accessory items, A/C, etc.) should always be performed Click here.

  • Before removing the ECM and the peripheral parts, wait at least 3 minute after turning the ignition switch off (If the cooling fan is operating, remove the ECM and the peripheral parts after the fan stops.).

PROCEDURE


  1. INSPECT WATER TEMPERATURE WARNING LIGHT (VOLTAGE)


    1. A01385YE01

      Disconnect the 3G and 3H instrument panel J/B connectors.

    2. Turn the ignition switch to the ON position.

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

      Standard voltage
      Tester Connection Specified Condition
      Instrument panel J/B (3G-4) - Body ground 11 to 14 V
      Instrument panel J/B (3H-9) - Body ground 11 to 14 V

    NG

    CHECK AND REPAIR HARNESS AND CONNECTOR (BATTERY - INSTRUMENT PANEL J/B)

    OK

  2. CHECK HARNESS AND CONNECTOR (COMBINATION METER - BODY GROUND)


    1. A0138ALE01

      Disconnect the 3K instrument panel J/B connector.

    2. Disconnect the C1 combination meter connector.

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

      Standard resistance
      Tester Connection Specified Condition
      Instrument panel J/B (3K-1) - Body ground Below 1 Ω
      Combination meter (C1-17) - Body ground Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECM)


    1. A0138CRE01

      Disconnect the B54 ECM connector.

    2. Disconnect the A22 combination meter connector.

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

      Standard resistance
      Check for open
      Tester Connection Specified Condition
      HOT (B54-20) - Combination meter (A22-7) Below 1 Ω
      Check for short
      Tester Connection Specified Condition
      HOT (B54-20) or Combination meter (A22-7) - Body ground 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. REPLACE COMBINATION METER


    NEXT

  5. CHECK IF DTC RECURS (P1608)


    1. Connect the intelligent tester to the DLC3.

    2. Clear the DTC Click here.

    3. Turn the ignition switch to the ON position and turn the intelligent tester on.

    4. Select the following menu items: Powertrain / Engine and ECT / DTC.

    5. Read the DTCs displayed on the intelligent tester.

      Result
      Display (DTC output) Proceed To
      No output A
      P1608 B

    B

    REPLACE ECM

    A

    END