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It sounds like everything is working but the blend air door. You are correct. It is a cable. Here are the directions for replacement of the cable. Before getting a new cable, make sure nothing has come loose or broken. The attached pictures correlate with the directions.
1997 Dodge or Ram Truck RAM 1500 Truck 4WD V8-5.2L VIN Y
Temperature Control Cable Replacement
Vehicle Heating and Air Conditioning Air Door Air Door Cable Service and Repair Procedures Temperature Control Cable Replacement
TEMPERATURE CONTROL CABLE REPLACEMENT
Fig 43 Temperature Control Cable (Heater-A/C Housing End)
1. Lower the steering column and roll down the instrument panel.
2. Disconnect the temperature control cable from the top of the heater-A/C housing.
3. Remove the heater-A/C control.
Fig 44 Temperature Control Cable (Heater-A/C Control End)
4. Disconnect the temperature control cable from the beater-AC control.
1. Connect the temperature control cable to the heater-A/C control.
2. Install the heater-A/C control.
3. Connect the temperature control cable to the top of the heater-A/C housing.
4. Install the instrument panel and raise the steering column.
Let me know if this helps or if you have other questions.
Images (Click to enlarge)
Friday, October 25th, 2019 AT 9:36 PM