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:
Inspection
1. Inspect defogger relay (marking: def)
Remove the defogger relay from the instrument panel
j/b.
inspect the defogger relay.
Standard:
If the result is not as specified, replace the relay ...
Ecm (1zz–fe)
Replacement
1. Disconnect battery negative terminal
2. Remove glove compartment door assy
3. Remove ecm
Remove the 2 clips using a clip remover. Then, open the
cover.
Disconnect the 4 ecm connectors.
remove the wire harness from the wire harness clamp.
Remove the 2 ...
Back up lamp assy lh
Replacement
1. Remove back up lamp assy lh
Remove the service hole cover.
remove the 2 nuts and disconnect the connector.
Using a mouldingremover, remove the 2 clips and back
up light assy lh.
2. Install back up lamp assy lh
Set the 2 clips on the back up ligh ...


