Toyota Corolla Quiz
Diagnostics

Circuit description

In this manual: Diagnostics
Introduction — 31Preparation — 32Service specifications — 19Diagnostics — 497Engine control system — 6Fuel — 13Emission control — 28Exhaust — 3Cooling — 13Lubrication — 7Ignition — 3Starting & charging — 13Front suspension — 12Rear suspension — 9Tire & wheel — 1Drive shaft / propeller shaft — 15Brake — 42Automatic transmission / trans — 47Clutch — 19Steering column — 9Power steering — 11Heater & air conditioner — 20Supplemental restraint system — 27Seat belt — 12Lighting — 18Wiper & washer — 9Audio & visual — 12Wiring — 1Communication system — 1Windshield/windowglass/mirror — 31Seat — 10Theft deterrent & door lock — 10Sliding roof/convertible — 8Engine hood/door — 12Exterior/interior trim — 20Vehicle control system — 1Cruise control — 5Maintenance — 8
6steps
~36min
2/5difficulty
Done 0 of 6

Refer to dtc p0115

Dtc no. Dtc detection condition Trouble area
P0116 If engine coolant temperature (ect) was between 35 c (95 °F) and 60 c (140 °F) when starting the engine, and also conditions (a) and (b) are met:
  1. vehicle has run with acceleration and deceleration
  2. etc still remains within 3 c (5.4 °F) of the starting temperature (2 trip detection logic)
  • Engine coolant temperature sensor
If engine coolant temperature (ect) was more than 60 c when starting the engine, and also conditions (a) and (b) are met:
  1. vehicle has run with acceleration and deceleration
  2. ect still remains within 1 c (1.8 °F) of the starting temperature (6 trip detection logic)
Monitor description

The engine coolant temperature (ect) sensor is used to monitor the engine coolant temperature. The ect sensor has a thermistor that varies its resistance depending on the temperature of the engine coolant. When the coolant temperature is low, the resistance in the thermistor increases. When the temperature is high, the resistance drops. The variations in resistance are reflected in the voltage output from the sensor. The ecm monitors the sensor voltage and uses this value to calculate the engine coolant temperature. When the sensor output voltage deviates from the normal operating range, the ecm interprets this as a fault in the ect sensor and sets a dtc.

Examples:

  1. upon starting the engine, the coolant temperature (ect) was between 35 c (95 °F) and 60 c (140 °F).

    If after driving for 250 seconds, the ect still remains within 3 c (5.4 °F) of the staring temperature, a dtc will be set. (2 Trip detection logic)

  2. upon starting the engine, the coolant temperature (ect) was over 60 c (140 °F). If after driving for 250 seconds, the ect still remains within 1 c (1.8 °F) of the starting temperature, a dtc will be set. (6 Trip detection logic)
Monitor strategy
Toyota Corolla. Monitor strategy
Typical enabling conditions
Toyota Corolla. Typical enabling conditions
Typical malfunction thresholds
Toyota Corolla. Typical malfunction thresholds
Component operating range
Toyota Corolla. Component operating range
Wiring diagram

Refer to dtc p0115

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