Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Sfi system / Insufficient coolant temperature
for closed loop fuel control / Inspection procedure
Toyota Corolla (E120): 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 tool. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air–fuel ratio was lean or rich, etc. At the time of the malfunction.
1 Check other dtc output(in addition to dtc p0125)
- Connect the hand–held tester or the obd ii scan tool to the dlc3.
- turn the ignition switch on and push the hand–held tester or the obd ii scan tool main switch on.
- select the item ”diagnosis / enhanced obd ii / dtc info / current codes”.
- read the dtcs.
Result:

Hint
: if any other codes besides p0125 are output, perform the troubleshooting for those dtcs first.


2 Inspect thermostat


Replace engine coolant temperature sensor
Other materials:
Other functions
■ Switching between outside air and recirculated air modes
Press .
The mode switches between outside air mode (indicator off) and recirculated air
mode (indicator on) each time is pressed.
■ Defogging the windshield
Defoggers are used to defog the windshield and front side windows ...
Inspection procedure
Hint:
this dtc chart is on the premise that the engine is cranked normally.
If the engine is not cranked, proceed
to the problem symptoms table on page 05–42.
Read freeze frame data using the hand-held tester or the obd ii scan
tool. Freeze frame data records
the engine conditions ...
On–vehicle inspection
1. Inspection throttle body idle speed control valve assy
Notice:
it is impossible to check the resister value and the operation
of isc valve by itself, because the isc valve
has an ic circuit inside it, which transforms the duty
signal from the ecm to the derive signal.
After check ...


