Toyota Corolla Repair Manual: Coolant thermostat (coolant temperature below thermostat regulating temperature)
Dtc p0128 coolant thermostat (coolant temperature below thermostat regulating temperature)
Hint
: this is the purpose of the ”thermostat” malfunction detection.
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, ...
Circuit description
If the engine coolant temperature (ect) does not reach 75°c (167°f) despite
sufficient warm – up time has
elapsed.
Dtc no
Dtc detection condition
Trouble area
P01 ...
Other materials:
Inspection procedure
1 Inspect fuse(ecu–ig fuse)
Remove ecu–ig fuse from the instrument panel j/b.
check continuity of ecu–ig fuse.
Ok:
continuity
2 Inspect battery
Ok:
voltage: 10 – 14 v
3 Inspect skid control ecu connector(ig1 terminal voltage)
In case of using hand–held tester:
...
Evap monitor (vacuum pressure monitor)
Notice:
a cold soak must be performed prior to conducting the drive pattern to complete
the internal pressure
readiness monitor.
Cold soak preconditions
The monitor will not run unless:
mil is off.
Fuel level is approximately 1/2 to 3/4.
Altitude is 7800 feet (2400 m) or less.
...
Glossary of tire terminology
*: Table 1 - Occupant loading and distribution for vehicle normal load for various
designated seating capacities
...