Control Panel - Pontiac FIREBIRD 1972 Service Manual

1B-50 1972 PONTIAC SERVICE MANUAL
Apply
+
12 volts DC (available at BAT terminal of
fuse block) to terminal number 1 (one) only. This will
cycle the programmer to the full cold position. Allow
minimum time of 30 seconds for this operation.
Remove
+
12 volts DC from terminal number one (1)
and apply to terminal
#
8 only. This will cycle the
programmer to the A/C park position. A minimum
time of 15 seconds should be allowed for this operat-
ion.
Push lower diverter door inward if necessary and
install tool J 22667-01 in hole in heater core and case
assembly (Fig. 1B-49).
Position temperature door against tool, attach link to
programmer arm and tighten adjusting screw.
Apply
+
12 volts DC to terminal
#
1 only. Program-
mer will cycle to full cold allowing removal of tool.
Connect programmer connector.
Replace glove compartment and cold air duct.
CONTROL PANEL
REMOVE AND REPLACE
Control panels for Automatic Temperature Control sys-
tems can be removed by using procedures for A/C control
panel replacement. These procedures are in section 1A.
Fig. 18-49 Tool J 22667-01 Installed
COWROL PANEL COMPONENTS
Several items on the Automatic Temperature Control
panel are serviced. They include the rotary vacuum valve,
switches, variable resistor, etc.
Figs. 1B-50 and 1B-51 show the B and G Series panels
respectively and should be referred to when servicing in-
dividual components.
VARIABLE RESISTOR (POTENTIOMETER)
-
G
SERIES
Two methods of adjusting the temperature control varia-
ble resistor are available. Use the first method to adjust the
unit in the car and the second to adjust the variable resis-
tor after installing a new one.
When replacing potentiometer note position and scribe
alignment marks to assure proper positioning of new
potentiometer.
ADJUST IN CAR:
1. To lower the in-car temperature to suit owner prefer-
ence, insert tool J 23187 in system selector lever slot
(Fig. 1B-52).
2. Engage teeth on variable resistor and pull towards
you to lower outlet temperature.
3. To raise the in-car temperature, push the variable
resistor gear away from you with tool J 23187.
ADJUST ON BENCH:
1. Connect a calibrated ohm meter across the two green
leads at the potentiometer connector. Set tempera-
ture lever on control panel at "75" and observe me-
ter. Meter should read "560 ohms".
2. If meter reading is not 560 ohms, lift the small plastic
gear on potentiometer shaft from gear teeth on plastic
cam attached to temperature lever.
3. Rotate small gear in direction which causes meter
indication to approach 560 ohms. Stop when 560
ohms is reached.
4. Push small plastic gear down onto shaft until gear
teeth engage teeth on the temperature cam.
5. Stake end of potentiometer shaft (center punch may
be used) to retain plastic gear.
TEMPERATURE DIAL CALIBRATION
-
B SERIES
Be sure to allow sufficient time for car engine to warm up
and ATC system to turn-on before attempting calibration.