Last Modified: 07-31-2024 |
6.11:8.1.0 |
Doc ID: RM100000001GJ5U |
Model Year Start: 2020 |
Model: Corolla |
Prod Date Range: [01/2019 - 04/2020] |
Title: 2ZR-FXE (ENGINE CONTROL): SFI SYSTEM: P012500; Insufficient Coolant Temperature for Closed Loop Fuel Control; 2020 MY Corolla Corolla HV [01/2019 - 04/2020] |
DTC
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P012500
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Insufficient Coolant Temperature for Closed Loop Fuel Control
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DESCRIPTION
Refer to DTC P011511.
Click here
DTC No.
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Detection Item
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DTC Detection Condition
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Trouble Area
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MIL
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Memory
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Note
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P012500
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Insufficient Coolant Temperature for Closed Loop Fuel Control
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The engine coolant temperature does not reach the closed loop enabling temperature for 20 minutes (this period varies with the engine coolant temperature at engine start) (2 trip detection logic).
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-
Engine cooling system
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Engine coolant temperature sensor
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Water inlet with thermostat sub-assembly (thermostat)
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Comes on
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DTC stored
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-
SAE Code: P0125
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DTC for Mexico Models: Does not apply
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MONITOR DESCRIPTION
The resistance of the engine coolant temperature sensor varies in proportion to the actual engine coolant temperature. The ECM supplies a constant voltage to the sensor and monitors the signal output voltage of the sensor. The signal output voltage varies according to the changing resistance of the sensor. After the engine is started, the engine coolant temperature is monitored by this signal. If the engine coolant temperature sensor indicates that the engine is not yet warm enough for closed loop fuel control, despite a specified period of time having elapsed since the engine was started, the ECM interprets this as a malfunction in the sensor or engine cooling system, illuminates the MIL and stores this DTC.
Example:
When the engine coolant temperature is -3.33°C (26°F) or higher at engine start: After approximately 103 seconds of running time, the engine coolant temperature sensor still indicates that the engine is not warm enough to begin closed-loop fuel (air fuel ratio feedback) control. The ECM interprets this as a malfunction in the sensor or cooling system and stores the DTC.
MONITOR STRATEGY
Related DTCs
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P0125: Insufficient engine coolant temperature for closed loop fuel control
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Required Sensors/Components (Main)
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Engine coolant temperature sensor
Thermostat
Engine cooling system
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Required Sensors/Components (Related)
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-
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Frequency of Operation
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Once per driving cycle
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Duration
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103 seconds: Engine coolant temperature at engine start is -3.33°C (26°F) or higher
289 seconds: Engine coolant temperature at engine start is -14.44°C (6°F) or higher, and less than -3.33°C (26°F)
1200 seconds: Engine coolant temperature at engine start is less than -14.44°C (6°F)
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MIL Operation
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2 driving cycles
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Sequence of Operation
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None
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TYPICAL ENABLING CONDITIONS
Monitor runs whenever the following DTCs are not stored
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None
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All of the following conditions are met
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-
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Thermostat fail (P0128)
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Not detected
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Intake air temperature sensor circuit fail (P0112, P0113)
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Not detected
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Engine coolant temperature sensor circuit fail (P0117, P0118)
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Not detected
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Mass air flow meter circuit fail (P0102, P0103)
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Not detected
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TYPICAL MALFUNCTION THRESHOLDS
Time until actual engine coolant temperature reaches closed loop fuel control enabling temperature
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103 seconds: Engine coolant temperature at engine start is -3.33°C (26°F) or higher
289 seconds: Engine coolant temperature at engine start is -14.44°C (6°F) or higher, and less than -3.33°C (26°F)
1200 seconds: Engine coolant temperature at engine start is less than -14.44°C (6°F)
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CONFIRMATION DRIVING PATTERN
HINT:
-
After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.
Click here
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When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.
Click here
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Leave the vehicle outside overnight.
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Connect the Techstream to the DLC3.
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Turn the power switch on (IG).
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Turn the Techstream on.
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Enter the following menus: Powertrain / Engine / Data List / Coolant Temperature.
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Check that the engine coolant temperature is 10°C (50°F) or less.
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Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
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Turn the power switch off and wait for at least 30 seconds.
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Turn the power switch on (IG).
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Turn the Techstream on.
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Put the engine in Inspection Mode (Maintenance Mode).
Click here
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Start the engine [A].
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Wait 21 minutes or more [B].
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Enter the following menus: Powertrain / Engine / Trouble Codes [C].
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Read the pending DTCs.
HINT:
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If a pending DTC is output, the system is malfunctioning.
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If a pending DTC is not output, perform the following procedure.
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Enter the following menus: Powertrain / Engine / Utility / All Readiness.
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Input the DTC: P012500.
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Check the DTC judgment result.
Techstream Display
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Description
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NORMAL
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DTC judgment completed
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System normal
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ABNORMAL
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-
DTC judgment completed
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System abnormal
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INCOMPLETE
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-
DTC judgment not completed
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Perform driving pattern after confirming DTC enabling conditions
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WIRING DIAGRAM
Refer to DTC P011511.
Click here
CAUTION / NOTICE / HINT
HINT:
-
If any of DTCs P011511, P011515 or P01152A are output simultaneously with DTC P012500, the engine coolant temperature sensor may have an open or a short circuit. Troubleshoot those DTCs first.
-
Read freeze frame data using the Techstream. 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.
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CHECK ANY OTHER DTCS OUTPUT (IN ADDITION DTC P012500)
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(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine / Trouble Codes.
(e) Read the DTCs.
Powertrain > Engine > Trouble Codes
Result
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Proceed to
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DTC P012500 is output
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A
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DTC P012500 and other DTCs are output
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B
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HINT:
If any DTCs other than P012500 are output, troubleshoot those DTCs first.
A
|
|
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2.
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INSPECT WATER INLET WITH THERMOSTAT SUB-ASSEMBLY
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(a) Inspect the water inlet with thermostat sub-assembly (thermostat opening temperature).
Click here
OK
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|
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3.
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CHECK ENGINE COOLING SYSTEM
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(a) Check for defects in the engine cooling system that might cause the system to be too cold, such as abnormal cooling fan operation or any modifications.
HINT:
Perform "Inspection After Repair" after replacing the engine coolant temperature sensor.
Click here
NG |
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REPAIR OR REPLACE ENGINE COOLING SYSTEM
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