Pontiac firebird 1968 - Page 75

1B-2
1968 PONTIAC SERVICE MANUAL
RECIRC. CLUTCH SWITCH MASTER
CONTROL CLUTCH
Fig. 1B-2 Bottom View Control Panel
7. To replace, reverse removal procedure.
TEMPERATURE CONTROL SWITCH VARIABLE
RESISTOR ADJUSTMENT
1. Connect on ohmmeter across resistor.
2. Calibrate ohmmeter.
3. Turn temperature dial until the meter reads
560 ohms.
4. Disengage the friction clutch by pulling outward
on shaft.
5. Rotate shaft until it reads exactly 75 (Fig.
1B-33).
NOTE: An alternate procedure for this adjust-
ment is to use Automatic Temperature Control
Tester, J 22684.
1/8" SCRIBE LINES ON ROTATING DRUM
PROGRAMMER REPLACEMENT (Fig. IB-A7)
1. Remove cold air duct and glove compartment.
2. Remove programmer link screw.
3. Remove screw retaining vacuum harness con-
nector to programmer.
4. Disconnect two electrical connectors.
5. Remove programmer retaining screws.
6. Pull programmer carefully rearward so as not
to break heat sensor.
7. To replace, reverse removal procedure.
ADJUST DOOR LINK
1. Remove distribution duct.
2. Remove glove compartment.
3. Loosen screw retaining link to programmer
arm and separate the units.
4. Disconnect programmer connector shown in
Fig. 1B-5*
5. With ignition on and OFF button depressed on
control head, ground terminals 2, 3 and 4 (Fig.
IB-6 identifies terminals).
6. Apply +12 volts DC (available at BAT terminal
of fuse block) to terminal number 2 only. This will
cycle programmer to full cold position.
7. Remove +12 volts DC from terminal number 1
and apply to terminal No. 8 only. This will cycle
programmer to the AC park position.
8. Push lower diverter door inward if necessary
and install tool J 22667 in hole in heater core and
case assembly (Fig. 1B-7).
9. Position temperature door against tool, attach
link to programmer arm and tighten adjusting screw.
10. Apply +12 volts DC to terminal number 1 only.
Programmer will cycle to full cold allowing removal
of tool.
11. Connect programmer connector.
12. Replace glove compartment and distribution
duct.
PROGRAMMER SERVICE
REMOVAL
Fig. 1B-3 Control Window Adjustment
1. To remove programmer, remove positive bat-
tery terminal, remove glove compartment and dis-
connect harness from programmer.