DESCRIPTION
The engine is equipped with an engine coolant temperature sensor and an engine oil temperature sensor (engine oil pressure and temperature sensor). The engine coolant temperature sensor and engine oil temperature sensor (engine oil pressure and temperature sensor) each have a built-in thermistor. As the temperature decreases, the thermistor resistance increases and as the temperature increases, the thermistor resistance decreases. The voltages at the respective terminals of the ECM change in accordance with the changes in the resistance of the thermistors. The ECM performs control based on these voltages.
DTC No. | Detection Item |
DTC Detection Condition | Trouble Area |
MIL | Note |
---|---|---|---|---|---|
P012F62 | Engine Coolant Temperature/Engine Oil Temperature Signal Compare Failure |
All of the following conditions are met (2 trip detection logic):
|
| Comes on |
|
MONITOR DESCRIPTION
After the engine has stopped for 5 hours or more, the ECM monitors the voltage of the engine coolant temperature sensor and engine oil temperature sensor (engine oil pressure and temperature sensor). If the difference between the readings of the engine coolant temperature and engine oil temperature is higher than 20°C (68°F), the ECM determines that there is a malfunction in the engine coolant temperature sensor circuit or engine oil temperature sensor (engine oil pressure and temperature sensor) circuit, and stores a DTC and illuminates the MIL.
MONITOR STRATEGY
Related DTCs | P012F: Engine coolant temperature sensor / Engine oil temperature sensor rationality |
Required Sensors/Components (Main) | Engine coolant temperature sensor Engine oil temperature sensor |
Required Sensors/Components (Related) |
- |
Frequency of Operation |
Once per driving cycle |
Duration |
Within 60 seconds |
MIL Operation |
2 driving cycles |
Sequence of Operation |
None |
TYPICAL ENABLING CONDITIONS
All of the following conditions are met |
- |
Time after ignition switch off |
5 hours or more |
Engine coolant temperature |
-10°C (14°F) or higher |
Engine oil temperature |
-10°C (14°F) or higher |
Time after ECM started by soak timer |
0.5 seconds or more |
Ignition switch | Off |
Auxiliary battery voltage | Higher than 8 V |
Engine coolant temperature sensor circuit fail (P0117, P0118) |
Not detected |
Engine oil temperature sensor circuit fail (P0197, P0198) |
Not detected |
Soak timer fail (P2610) |
Not detected |
TYPICAL MALFUNCTION THRESHOLDS
Deviated engine coolant temperature and engine oil temperature |
Less than -20°C (-4°F), or higher than 20°C (68°F) |
CONFIRMATION DRIVING PATTERN
HINT:
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HINT:
GTS Display |
Description |
---|---|
NORMAL |
|
ABNORMAL |
|
INCOMPLETE |
|
HINT:
The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.
CAUTION / NOTICE / HINT
NOTICE:
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(Select Powertrain in Health Check and then check the time stamp data.)
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Click here
HINT:
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. |
CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P012F62) |
(a) Read the DTCs and record the Freeze Frame Data.
Powertrain > Engine > Trouble Codes
Result | Proceed to |
---|---|
DTC P012F62 is output |
A |
DTC P012F62 and other DTCs are output |
B |
HINT:
If any DTCs other than P012F62 are output, troubleshoot those DTCs first.
B | GO TO DTC CHART |
|
2. |
CHECK FREEZE FRAME DATA (COOLANT TEMPERATURE AND INTAKE AIR TEMPERATURE) |
(a) Using the GTS, read the values displayed in the Freeze Frame Data recorded in step 1.
Powertrain > Engine > DTC(P012F62) > Freeze Frame Data
Tester Display |
---|
Coolant Temperature |
Intake Air Temperature |
(b) Read the value displayed on the GTS.
Standard:
GTS Display | Specified Condition |
---|---|
Difference between the Coolant Temperature and the Intake Air Temperature |
Within 15°C (59°F) |
HINT:
Click here
NG | REPLACE ENGINE COOLANT TEMPERATURE SENSOR |
|
3. |
CHECK FREEZE FRAME DATA (ENGINE OIL TEMPERATURE SENSOR AND INTAKE AIR TEMPERATURE) |
(a) Using the GTS, read the values displayed in the freeze frame data recorded in step 1.
Powertrain > Engine > DTC(P012F62) > Freeze Frame Data
Tester Display |
---|
Engine Oil Temperature Sensor |
Intake Air Temperature |
(b) Read the value displayed on the GTS.
Standard:
GTS Display | Specified Condition |
---|---|
Difference between the Engine Oil Temperature Sensor and the Intake Air Temperature |
Within 15°C (59°F) |
HINT:
When the engine is cold, the value of the engine coolant temperature, engine oil temperature and intake air temperature should be approximately the same.
OK | REPLACE ECM |
NG | REPLACE ENGINE OIL TEMPERATURE SENSOR (ENGINE OIL PRESSURE AND TEMPERATURE SENSOR) |