Control Module HVAC: Description and Operation

1984 Oldsmobile 88 Custom Cruiser V8-307 5.0L VIN Y 4-bblSECTION Description and Operation

Programmer assembly, front view:




Programmer assembly, rear view:





The programmer, Figs. 2 and 3, consists of a compensator assembly, a vacuum motor, a vacuum checking relay, the output linkage and control linkage. The programmer is mounted on the A/C heater case and is connected to the temperature door by means of a threaded rod from the heater case. There are three input connections to the programmer.

1. The vacuum connection from the vacuum harness supplies engine vacuum relay.
2. The temperature control cable from the control panel attaches to the control lever of the programmer to position the programmer for the desired comfort level.
3. The in-car air source hose is connected to the compensator assembly. This provides a sample of in-car air temperature to the programmer, allowing regulation of air outlet temperature to compensate for temperature changes inside the vehicle.



RENDER: 1.0x

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