Diagnosis And Testing - On-Board Diagnostics
WARNING: This page is about a different car, the 2011 RAM Pickup and 2011 RAM Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
All models are equipped with On-Board Diagnostics for certain cooling system components. Refer to appropriate Engine Performance Electrical Diagnostics article. If the Powertrain Control Module (PCM) detects low engine coolant temperature, it will record a Diagnostic Trouble Code (DTC) in the PCM memory. Do not change a thermostat for lack of heat as indicated by the instrument panel gauge or by poor heater performance unless a DTC is present. Refer to the appropriate Engine Performance Electrical Diagnostics article for other probable causes.