P0128

DTC P0128 THERMOSTAT FUNCTION

On Board Diagnosis Logic

On Board Diagnosis Logic:

Engine coolant temperature has not risen enough to open the thermostat even though the engine has run long enough.

This is due to a leak in the seal or the thermostat open stuck.

DTC Confirmation Procedure

NOTE: If "DTC Confirmation Procedure" has been previously conducted, always turn ignition switch "OFF" and wait at least 10 seconds before conducting the next test.

TESTING CONDITION:
For best results, perform at ambient temperature of -10°C (14°F) or higher.
For best results, perform at engine coolant temperature of -10°C (14°F) to 60°C (140°F).

WITH CONSULT-II
1. Replace thermostat with new one. .
Use only a genuine NISSAN thermostat as a replacement. If an incorrect thermostat is used, the MIL may come on.

2. Turn ignition switch "ON".
3. Select "COOLAN TEMP/S" in "DATA MONITOR" mode with CONSULT-II.
4. Check that the "COOLAN TEMP/S" is above 60°C (140°F). If it is below 60°C (140°F), go to following step. If it is above 60°C (140°F), stop engine and cool down the engine to less than 60°C (140°F), then retry from step 1.
5. Drive vehicle for 10 consecutive minutes under the following conditions.

VHCL SPEED SE 80 - 120 KM/H (50 - 75 MPH)

If 1st trip DTC is detected, go to "Diagnostic Procedure" below.

WITH GST
1. Follow the procedure "WITH CONSULT-II" above.

Diagnostic Procedure Step 1:

Diagnostic Procedure