P0125

Electrical Diagram:

CIRCUIT DESCRIPTION

The PCM monitors the ECT sensor in order to determine how long it takes the engine to reach the coolant temperature required for Closed Loop operation. DTC P0125 sets if the PCM determines that the engine does not reach Closed Loop temperature in a specified amount of time. This test will not run if either the intake air or engine coolant temperature is too low at start up. The PCM will only run this DTC on a cold start and only once per cold start.

CONDITIONS FOR SETTING THE DTC

^ DTCs P0112, P0113, P0117, P0118, not set

^ The engine coolant temperature is greater than 10°C (50°F), but less than 40°C (104°F) at start-up

^ The intake air temperature is greater than 10°C (50°F)

^ The vehicle speed is greater than 1.6 km/h (1 mph)

^ The closed loop coolant temperature of 34°C (93°F) is not reached within a predetermined time. The maximum allowable time depends on the start-up coolant temperature and the amount of airflow into the engine. The range for the time is from 2 minutes and 20 seconds to 5 minutes

ACTION TAKEN WHEN THE DTC SETS

^ The PCM illuminates the Malfunction Indicator Lamp on the second consecutive drive trip that the diagnostic runs and fails.

^ The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive drive trip, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure records.

CONDITIONS FOR CLEARING THE MIL/DTC

^ A History DTC clears after forty consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures.

^ The PCM battery voltage is interrupted.

^ Use a scan tool in order to clear the MIL/DTC.

DIAGNOSTIC AIDS

^ Using the Freeze Frame and/or Failure Records data may aid in locating an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame and/or Failure Records data can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can also help determine how many ignition cycles the diagnostic reported a pass and/or a fail. Operate the vehicle within the same freeze frame conditions (RPM, load, vehicle speed, temperature etc.) that you observed. This will isolate when the DTC failed. For an intermittent condition, refer to Symptoms. Testing and Inspection

^ If the engine has sat overnight, the engine coolant temperature and intake air temperature values should display within a few degrees of each other. If the temperatures are not within 3°C (5°F), refer to Temperature vs Resistance. Specifications

^ If you determine that the DTC occurs intermittently, performing the P1114 or P1115 diagnostics table may isolate the cause of the fault. P1114 P1115

^ An engine coolant temperature exceeding 34°C (93°F), indicates that the engine is capable of reaching the proper temperature, but not necessarily in the correct amount of time. Repeat this diagnostic table on a cold engine, and measure the time required to reach the temperature threshold. When starting a cold engine, measure the amount of time it takes the engine to reach the specified temperature. The engine should reach the specified temperature within 5 minutes or less. If the engine does not reach the specified temperature within 5 minutes, check the following:

- Coolant level

- Thermostat operation

- Are fans on at all times?

- Refer to Service Category Cooling System for additional information.

TEST DESCRIPTION

The numbers below refer to the step numbers on the diagnostic table.

2. An ECT failure could cause a DTC P0125 to set, so correct any ECT DTCs that are set. For any test that requires probing the PCM or a component harness connector, use the Connector Test Adapter Kit J 35616-A. Using this kit prevents damage to the harness connector terminals.

6. If it is obvious that the engine is not reaching full operating temperature, for example the radiator hoses never get very warm, or there is a complaint of little or no heat from the heater, you can skip this step.

9. This DTC will not report a pass. The scan tool status for this DTC will never report a pass. The scan tool will only display when the diagnostic fails. The repair is not complete if the scan tool indicates that the diagnostic ran and failed.