
HINT:
This DTC relates to the thermostat.
DESCRIPTION
This DTC is set when the Engine Coolant Temperature (ECT) does not reach 75°C (167°F) despite sufficient engine warm-up time.

MONITOR DESCRIPTION

The ECM estimates the ECT based on the starting temperature, engine loads, and engine speeds. The ECM then compares the estimated temperature with the actual ECT. When the estimated ECT reaches 75°C (167°F), the ECM checks the actual ECT. If the actual ECT is less than 75°C (167°F), the ECM interprets this as a malfunction in the thermostat or the engine cooling system and sets the DTC.
MONITOR STRATEGY


TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

INSPECTION PROCEDURE
HINT:
Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air-fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.
1 CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0128)
(a) Connect the intelligent tester to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Turn the tester on.
(d) Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES.
(e) Read the DTCs.
Result 
HINT: If any DTCs other than P0128 are output, troubleshoot those DTCs first.

2 CHECK COOLING SYSTEM
(a) Check for defects in the cooling system that might cause the system to be too cold, such as abnormal radiator fan operation or any modifications.


3 INSPECT THERMOSTAT
(a) Remove the thermostat (See page CO-16).
(b) Check the valve opening temperature of the thermostat (See page CO-17).
Standard: 80 to 84°C (176 to 183°F)
HINT:
In addition to the above check, confirm that the valve is completely closed when the temperature is below the standard.
(c) Reinstall the thermostat (See page CO-17).

REPLACE ECM (See page ES-498)
Insufficient Coolant Temperature for Closed Loop Fuel Control
Oxygen Sensor CircuitInstallation
1. INSTALL CAMSHAFT TIMING OIL CONTROL VALVE ASSEMBLY (for Bank 2 Exhaust
Side)
Apply a light coat of engine oil to the new O-ring and
install it to the camshaft timing oil control valve.
Install the camshaft timing oil control valve
assembly with the bolt.
Torque: 10 N ...
Short to GND in Driver Side Squib Circuit
DTC B0102/11 Short to GND in Driver Side Squib Circuit
DESCRIPTION
The driver side squib circuit consists of the center airbag sensor assembly,
the spiral cable and the
steering pad.
The circuit instructs the SRS to deploy when deployment conditions are met.
DTC B0102/11 is recorded when ...
Key Lock-in Prevention Function does not Work Properly (Manual
Operation and Operation Interlocked with Key are Active)
DESCRIPTION
The un-lock warning switch turns ON when the key is inserted in the ignition
key cylinder. The courtesy
light switch turns ON when the driver side door is opened. These 2 switches are
monitored by the body
ECU.
In order to prevent the key from being locked in, the body ECU cont ...