Theory Of Operation
WARNING: This page is about a different car, the 2019 RAM 3500 HD and 2019 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.
The Mode and Temperature (Blend) Doors are opened and closed with electric actuators that provide a position signal. There are five circuits that run between each actuator and the HVAC Module:
- 5-Volt Supply
- Position Signal
- Sensor Ground
- 12-Volt Driver Circuit 1
- 12-Volt Driver Circuit 2
The position signal is used by the HVAC module to monitor the door position. If the desired positions cannot be reached during normal operation, a DTC will set. All of the circuits are also monitored, either directly or indirectly, for open/short circuit faults.