Toyota Corolla (E120): Inspection procedure
Hint
: 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 cooling system
- Check that there is a defect in the cooling system which causes overcool, such as abnormal radiator fan operation, modified cooling system and so on.


2 Inspect thermostat


3 Check other dtc output(in addition to dtc p0128)
- 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 p0128 is output, perform the troubleshooting for those dtcs first.


Replace ecm
Other materials:
Replacement
1. Remove engine under cover rh
2. Remove cylinder head cover no.2
Remove the 2 screw, 3 clips and engine under cover.
3. Remove fan and generator v belt
Turn the v–ribbed belt tensioner slowly clockwise and
loosen it. Then, remove the fan and generator v belt and
put back ...
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 ...
Inspection procedure
1 Check side squib(rh) circuit(airbag sensor assy center – front
seat airbag assy rh)
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connectors between the airbag sensor
assy center and the front seat airbag assy ...


