P0125

Schematic:

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.

CONDITIONS FOR RUNNING THE DTC
^ DTCs P0112, P0113, P0117, P0118 not set
^ The engine is operating.
^ The engine coolant temperature is between -36°C (-33°F) and 40°C (104°F) at engine start-up.
^ The intake air temperature is more than -7°C (19°F).
^ The vehicle speed is more than 1.6km/h (1 mph).

CONDITIONS FOR SETTING THE DTC
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 22 minutes and 30 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ The PCM illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle 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 ignition cycle, 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
^ The PCM turns the Malfunction Indicator Lamp (MIL) OFF after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
^ A last test failed (current DTC) clears when the diagnostic runs and does not fail.
^ A History DTC clears after 40 consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures.
^ Use a scan tool in order to clear the MIL/DTC.

DIAGNOSTIC AIDS

IMPORTANT:
^ Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM connector gaskets when diagnosing/replacing the PCM. Ensure that the gaskets are installed correctly. The gaskets prevent contaminant intrusion into the PCM.
^ For any test that requires probing the PCM or component harness connectors, use the J 35616-A connector test adapter kit. Using this kit prevents any damage to the harness connector terminals. Refer to Using Connector Test Adapters in Diagrams.

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.

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

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, inspect for the following:
^ Coolant level: refer to Loss of Coolant in Engine Cooling.
^ Thermostat operation: Refer to Thermostat Diagnosis in Engine Cooling. Component Tests and General Diagnostics
^ Are fans on at all times? Refer to Electric Cooling Fan Diagnosis. Component Tests and General Diagnostics
^ Refer to Engine Falls To Reach Normal Operating Temperature in Engine Cooling.

For an intermittent condition, refer to Symptoms. Symptom Related Diagnostic Procedures

TEST DESCRIPTION

Steps 1 - 4:

Steps 5 - 10:

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.
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 concern of little or no heat from the heater, you can skip this step.