Toyota Corolla Repair Manual: 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)

1. Connect the hand–held tester or the obd ii scan tool to the dlc3.
2.  turn the ignition switch on and push the hand–held tester or the obd ii scan tool main switch on.
3. select the item ”diagnosis / enhanced obd ii / dtc info / current codes”.
4.  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