P0116
DTC P0116: Engine Coolant Temp. (ECT) Circuit Range / Performance Problem
Wiring Diagram
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure
WARNING:
- When performing a road test, select a place where there is no traffic or possibility of a traffic accident and very careful during testing to avoid occurrence of an accident.
- Road test should be carried out with 2 persons, a driver and tester, on a level road.
NOTE:
Check to make sure that the following conditions are satisfied when using this DTC confirmation procedure.
- Intake air temp.: -14 °C, 6.8 °F or higher
- Altitude (barometric pressure): 2020 m, 6650 ft or less (540 mmHg, 72 kPa or more)
1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch, clear DTC.
3) Start engine.
4) Drive vehicle at 40 mph (60 km/h) or higher for 20 min. or more.
5) Stop vehicle.
6) Check DTC and pending DTC.
DTC Troubleshooting
1.
Was "Engine System Check" performed?
YES
Go to Step 2.
NO
Go to Engine System Check Engine System Check.
2. Engine coolant temp. check.
With ignition switch turned OFF, install scan tool.
Turn ON ignition switch and check engine coolant temp. displayed on scan tool.
Warm up engine to normal operating temp. and check engine coolant temp. displayed on scan tool.
Does engine coolant temp. vary higher than 1 °C (1 °F) and rise higher than 70 °C (158 °F)?
YES
Intermittent trouble.
Check for intermittent referring to Intermittent and Poor Connection Inspection.
NO
Go to Step 3.
3. Thermostat check.
Is there a symptom due to thermostat remaining open (it takes a long time before vehicle heater becomes effective or before engine is warmed to normal operating temp., etc.)?
YES
Check thermostat referring to Thermostat Inspection.
NO
Go to Step 4.
4. Check wire harness.
Disconnect ECT sensor connector with ignition switch turned OFF.
Check for proper connection to ECT sensor at "ORN" and "LT GRN" wire terminals.
If OK, then with ignition switch ON.
Is voltage applied to "LT GRN" wire terminal about 4 - 6 V?
YES
Go to Step 7.
NO
Go to Step 5.
5. Check ECM voltage.
Disconnect connectors from ECM with ignition switch turned OFF.
Remove ECM from vehicle body and connect connectors to ECM.
Check proper connection of connector at "C46-12" wire terminals.
If OK, then turn ON ignition switch, check voltage between "C46-12" and body ground.
Is voltage about 4 - 6 V at each terminal?
YES
"LT GRN" wire open circuit.
If wire and connection are OK, go to Step 6.
NO
Go to Step 6.
6. Check wire circuit.
Disconnect connector from ECM with ignition switch turned OFF.
Measure resistance between "LT GRN" wire terminal and body ground.
Is resistance infinity?
YES
Go to Step 7.
NO
"LT GRN" wire shorted to ground circuit.
If wire are OK, substitute a known-good ECM and recheck.
7. Check wire circuit.
Turn ON ignition switch.
Check voltage between "LT GRN" wire terminal and body ground.
Is voltage about 0 V at each terminal?
YES
Go to Step 8.
NO
"LT GRN" wire shorted to power circuit.
If wire are OK, substitute a known-good ECM and recheck.
8. Check wire circuit.
Measure resistance between "C46-12" terminal and "LT GRN" wire terminal in ECT sensor connector with ignition switch turned OFF.
Is resistance below 5 ohms?
YES
Go to Step 9.
NO
"LT GRN" wire in high resistance circuit.
9. Check ground circuit.
Connect connector to ECM.
Check proper connection of ECT sensor at "ORN" wire terminal.
Measure resistance between "ORN" wire terminal in ECT sensor connector and body ground.
Is resistance below 10 ohms?
YES
Go to Step 11.
NO
Go to Step 10.
10. Check ground circuit.
Measure resistance between "C46-27" terminal and body ground.
Is resistance below 5 ohms?
YES
"ORN" wire open circuit or high resistance circuit.
Poor "C46-27" connection.
NO
Faulty ECM ground circuit.
If circuit are OK, substitute a known-good ECM and recheck.
11. Check ECT sensor.
Check ECT sensor according to Engine Coolant Temperature (ECT) Sensor Inspection Engine Coolant Temperature (ECT) Sensor Inspection.
Is it good condition?
YES
Substitute a known-good ECM and recheck.
NO
Replace ECT sensor.