Diesel Data: Automotive Repair

HVAC Overheated and Low Refrigerant Warning

The Driver Information Center (DIC) displays the A/C OFF... OVERHEATED message when the Powertrain Control Module (PCM) detects an AC overheating condition. The DIC displays the LOW A/C REFRIGERANT message when the PCM determines that the refrigerant is low. The DIC receives the HVAC information over the serial data line from the PCM via the instrument cluster.