The Engine Coolant
Temperature Sensor (ECTS) is located in the engine coolant passage of the
cylinder head for detecting the engine coolant temperature. The ECTS uses
a thermistor whose resistance changes with the temperature. The electrical
resistance of the ECTS decreases as the temperature increases, and
increases as the temperature decreases. The reference 5 V in the PCM is
supplied to the ECTS via a resistor in the PCM. That is, the resistor in
the PCM and the thermistor in the ECTS are connected in series. When the
resistance value of the thermistor in the ECTS changes according to the
engine coolant temperature, the output voltage also changes. During cold
engine operation the PCM increases the fuel injection duration and
controls the ignition timing using the information of engine coolant
temperature to avoid engine stalling and improve drivability.
Checking the coolant
temperature under detecting condition, if the coolant temperature exceeds
the threshold temperature under normal operation loads, PCM sets P0217.
MIL(Malfunction Indication Lamp) turns on when the malfunction lasts till
consecutive 2 driving cycle.
Item
|
Detecting
Condition
|
Possible cause
|
DTC
Strategy
|
| •
|
Monitor the coolant
temperature | |
|
Enable
Conditions
|
| •
|
Coolant sensor is
normal |
| •
|
No disabling faults present(DTCs related
to MAFS/MAPS, catalyst, fuel system or engine oil temperature
sensor) |
| •
|
Coolant Temperature at startup <
45°C( 113 °F) |
| •
|
Coolant temperature > 50°C( 122
°F) |
| •
|
Intake air temperature < 35°C( 95
°F) | |
Thresh old
value
|
| •
|
Coolant temperature ≥ 110°C (230
°F)(Average airflow < 30 g/sec and filtered airflow < 50
g/sec) | |
Diagnosis
Time
|
| •
|
Once per driving cycle ( about 2
minutes) | |
MIL On
Condition
|
|
Temp. (°C/°F)
|
Resistance (kΩ)
|
Temp. (°C/°F)
|
Resistance
(kΩ)
|
-40(-40)
|
48.14
|
40(104)
|
1.15
|
-20(-4)
|
14.13 ~
16.83
|
60(140)
|
0.59
|
0(32)
|
5.79
|
80(176)
|
0.32
|
20(68)
|
2.31 ~
2.59
|
|
|
| 1. |
Check DTC Status
| (1) |
Connect scantool to Data Link
Connector(DLC). |
| (3) |
Select "DTC" button, and then Press "DTC
Status" to check DTC's information from the DTCs
menu. |
| (4) |
Read "DTC Status"
parameter.
|
| (5) |
Is parameter displayed "Present
fault"?
|
|
▶ Go
to "Component Inspection" procedure.
|
|
|
▶
Fault is intermittent, go to "Verification of vehicle
Repair"
procedure.
|
| |
Check ECTS Resistance
| 1. |
IG "OFF" and disconnect ECTS
connector. |
| 2. |
Measure resistance between signal and ground
terminals of ECTS connector as the temperature rises.
Specificaton :
Temp.
(°C/°F)
|
Resistance
(kΩ)
|
-40(-40)
|
48.14
|
-20(-4)
|
14.13
~ 16.83
|
0(32)
|
5.79
|
20(68)
|
2.31 ~
2.59
|
40(104)
|
1.15
|
60(140)
|
0.59
|
80(176)
|
0.32
|
|
| 3. |
Are the measured resistance within
specification?
|
|
▶ Clear DTC
and Test-drive under enable conditions
above-mentioned.
After the test, If
this DTC is set, recheck it thoroughly. If not, it is
intermittent fault, go to "Verification of vehicle Repair"
procedure.
|
|
|
▶
Substitute with a known - good ECTS and check for proper
operation. If the problem is corrected, Go to "Verification of
Vehicle
Repair"procedure.
|
|
| Verification Of Vehicle
Repair |
After a repair, it is
essential to verify that the fault has been corrected.
| 1. |
Connect scantool and select "DTC"
button. |
| 2. |
Press "DTC Status" button and confirm that
"DTC Readiness Flag" indicates "Completed". If not, drive the
vehicle within conditions noted in the freeze frame data or enable
conditions |
| 3. |
Read "DTC Status"
parameter |
| 4. |
Is parameter displayed "History(Not Present)
fault"?
|
|
▶ System
performing to specification at this time. Clear the
DTC
|
|
|
▶ Go to the
applicable troubleshooting
procedure.
|
|
