COMPONENT LOCATION
GENERAL DESCRIPTION
ECTS consists of negative temperature coefficient thermistor. It is installed in coolant line of cylinder head and senses engine coolant temperature. ECM performs fuel injection correction, cooling fan control and glow operating period control according to coolant temperature informations. Especially, ECTS is closely related to fuel injection correction when engine is not warmed up, thus, turning engine at this moment is much difficult at a failure of ECTS. When engine is operating at a failure or ECTS, ECM controls fuel injection regarding coolant temperature as 80? and coolant temperature is regarded as -10? during cranking. Cooling fan which is controlled according to coolant temperature operates at HIGH-MODE to prevent engine from overheating. and supplementry heater is deactivated.
DTC DESCRIPTION
P0118 is set when the voltage above 4.97V - maximum output voltage of Cooling Temperature Sensor - is detected for more than 2.0 sec. This code is due to 1) open or 2) short to ground or 3) short to battery in ECTS signal circuit.
DTC DETECTING CONDITION
Item | Detecting Condition | Possible Cause |
DTC Strategy | Voltage Monitoring
| ECTS circuit ECTS component
|
Enable Conditions | Ignition "ON"
|
Threshold Value | When output signal is above the maximum value ( above 4.97V )
|
Diagnostic Time | 2.0 sec.
|
Fail Safe | Fuel Cut | NO | A/C condensor fan control operation inhibited. PTC heater inhibited Cooling fan is fixed at HIGH-MODE during engine operation : temperature is fixed at 80? at cranking : temperature is fixed at -10?
|
EGR Off | NO |
Fuel Limit | NO |
MIL | NO |
MONITOR SCANTOOL DATA
Connect scantool to Data Link Cable (DLC)
Warm engine up to normal operating temperature
Turn "OFF" electrical devices and A/C.
Monitor " ECTS " parameter on the scantool.
TERMINAL AND CONNECTOR INSPECTION
Electrical systems consist of a lot of harness and connectors, poor connection of terminals can cause various problems and damge of component.
Perform checking procedure as follows.
Check damage of harness and terminals : Check terminals for contact resistance, corrosion and deformation.
Check connecting condition of ECM and component connector : Check terminal seperation, damage of locking device and connecting condition between terminal and wiring
noteDisconnect the pin which requires checking at mail connector and insert it to the terminal at female connector for checking connecting condition ( after checking, reconnect the pin at correct position )
Is the problem found?
? Repair the trouble causing part and go to "Verification of Vehicle Repair"
? Go to "Signal Circuit Inspection "
SIGNAL CIRCUIT INSPECTION
Check signal circuit voltage
Ignition "OFF", Turn Engine "OFF"
Disconnect ECTS connector(C311)
Ignition "ON"
Measure the voltage of terminal 3 of ECTS connector.
Is the measured voltage within the specification?
? Go to "Ground Circuit Inspection"
? Go to "2.Check open in signal circuit" as follows.
Check open in signal circuit
Ignition "OFF", Turn Engine "OFF"
Disconnect ECTS connector(C311) and ECM connector (C333-2)
Check continuity between ECTS connector terminal 3 and ECM connector 3
Is the measured resistance within the specification?
? Go to "3. Check short to battery in signal circuit" as follows.
? Repair open spots in signal circuit and go to "Verification of Vehicle Repair"
Check short to battery in signal circuit
Ignition "OFF", Turn Engine "OFF"
Disconnect ECTS connector(C311) and ECM connector (C333-2)
Measure the voltage of terminal 3 of ECTS connector.
Is abnormal voltage detected in the circuit with both connector disconnected?
? Repair short to battery and go to "Verification of Vehicle Repair" .
? Go to "Ground Circuit Inspection"
GROUND CIRCUIT INSPECTION
Ignition "OFF", Turn Engine "OFF"
Disconnect ECTS connector(C311)
Check continuity between ECTS connector terminal 1 and chassis ground.
Is the measured resistance within the specification?
? Go to "Component Inspection"
? Repair open spots in signal circuit and go to "Verification of Vehicle Repair"
COMPONENT INSPECTION
Ignition "OFF", Turn Engine "OFF"
Disconnect ECTS connector(C311)
Measure resistance between ECTS component terminal 1 and 3, referring to resistance characteristic table of specification of General information
Is the measured resistance at certain temperature within the specified resisance range at the temperature?
? Go to "Verification of Vehicle Rapair"
? Replace ECTS and go to "Verification of Vehicle Rapair"
VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault is corrected.
After connecting scantool select "Diagnostic Trouble Codes(DTCs)" mode to and then clear DTC.
Drive the vehicle within DTC Enable conditions in General information.
After selecting "Diagnostic Trouble Codes(DTCs)" mode and check DTC is recorded again.
Are any DTCs recorded ?
? Go to the DTC guide of recorded No. in scantool.
? System operates within specification.
SCHEMATIC DIAGRAM