OBD-II Diagnostic Trouble Code
P0128
Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)
P
Powertrain
engine / trans
engine / trans
0
Generic
SAE standard
SAE standard
1
Fuel & air metering
28
Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)
Severity · general guide
Moderate
Fix soon — usually won't strand you
Code type
Ram
System
Powertrain
Model
1500
Years
2009-2024