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:
Wiring diagram
1 Inspect terminal voltage(pi)
(a) turn
Turn the ignition switch to on.
measure voltage between terminal 5 (pi) of cruise control
ecu assy and body ground, when the cruise control main
switch button is on and off.
Ok:
2 Inspect combination meter assy
3 Check harn ...
Things you should know
■ If you notice any symptoms
If you notice any of the following symptoms, refer to the likely cause and the
solution, and re-check.
If the symptom is not resolved by the solution, have the vehicle inspected by
your Toyota dealer.
CAUTION
■When using the rear view monitor system ...
Replacement
1. Drain brake fluid
Notice:
wash the brake fluid off immediately if it comes into contact with any painted
surface.
2. Remove air cleaner cap sub–assy
3. Remove air cleaner case sub–assy
remove the air cleaner element, then remove the 3 bolts and air
cleaner case sub–assy.
...


