Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Sfi system / Engine coolant temp. Circuit
range/performance problem / Circuit description
Toyota Corolla (E120): Circuit description
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:
|
|
If engine coolant temperature (ect) was more than 60 c
when starting the engine, and also conditions (a) and (b) are
met:
|
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:
- 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)
- 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
Typical enabling conditions
Typical malfunction thresholds
Component operating range
Wiring diagram
Refer to dtc p0115
Other materials:
Driving support system
information display
■ Driving support system
information
Select to display the operational
status of the following systems:
Dynamic radar cruise control
LTA (Lane Tracing Assist)
LDA (Lane Departure Alert)
■ Navigation system-linked
display (if equipped)
Select to display the following
navigation system-linked ...
Before driving
Observe the following
before starting off in the
vehicle to ensure safety of
driving.
Floor mat
Use only floor mats designed
specifically for vehicles of the
same model and model year as
your vehicle. Fix them securely
in place onto the carpet.
1. Insert the retaining hooks
(clips) into the floor ma ...
Inspection procedure
Hint:
if dtcs p0115, p0116, p0117, p0118 and p0125 are output
simultaneously, the engine coolant temperature
sensor circuit may be open or short. Perform the troubleshooting of dtc
p0115, p0117 or
p0118 first.
Read freeze frame data using the hand-held tester or the obd ii scan
to ...