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:
On–vehicle inspection
1. Inspect w/receiver condenser assy
if a fin of the w/receiver condenser assy is dirty, clean it with
water and dry it with compressor air.
Notice:
do not damage the fin of the w/receiver condenser assy.
if a fin of the w/receiver condenser assy is bent, make it
straig ...
Diagnostics
Preparation
Sst
09816–30010
Oil pressure switch socket
Sfi system
09843–18040
Diagnosis check wire no.2
Sfi system
supplemental restraint
system
Recomended tools
09082–00040
Toyota electrical tester
Sfi system
supplemen ...
Circuit description
When the brake pedal is depressed, the stop lamp switch assy sends a signal
to the cruise control ecu assy.
When the cruise control ecu assy receives this signal, it cancels the cruise
control.
A fail–safe function is provided so that cancel functions normally, even if
there is a malfu ...


