Code U0108 on the 2022 Jeep Grand Cherokee indicates lost communication with the Heating, Ventilation, and Air Conditioning (HVAC) control module. This module manages climate control functions and communicates with other vehicle systems for temperature management.
HVAC Module Integration
The modern Grand Cherokee's HVAC system is fully integrated with the vehicle's CAN network. The HVAC module communicates with the engine computer for A/C compressor requests, the body control module for blower and lighting, and the infotainment system for user interface. Communication loss disrupts all these interactions.
Climate Control Symptoms
With U0108 present, the climate control system may be completely inoperative or function erratically. The Uconnect display may show HVAC errors or fail to control temperature settings. Automatic climate control won't function, and manual overrides may not work either. Defrost functionality loss creates a safety concern in cold weather.
Diagnostic Approach
The HVAC control module is typically behind the dashboard, integrated with or connected to the HVAC control unit. Check for power and ground at the module. Verify the Uconnect system isn't the source of the problem by checking its communication status. Wiring damage behind the dashboard from aftermarket installations or rodent damage can cause these faults.
Repair Considerations
Dashboard removal may be required for full HVAC module access. If the module requires replacement, it must be programmed using Stellantis diagnostic tools. The dual-zone or tri-zone climate system configuration must be properly coded during programming.