wiring diagram CHEVROLET CAMARO 1967 1.G Chassis Workshop Manual

HEATER
AND AIR
CONDITIONING
1A-13

AIR CONDITIONING

INDEX

Page

General Description
1A-13

Four-Season System
1A-13

Controls
1A-16

Comfortron System
. 1A-18

System Components
lA-19

Controls
1A-20

Universal System
. .
1A-21

Chevy
n
All-Weather System
•
1A-21

Corvette Four-Season System
. 1A-22

General Information
. . . 1A-26

Precautions
in
Handling R-12
1A-26

Precautions
in
Handling Refrigerant Lines
1A-28

Maintaining Chemical Stability
in the

Refrigeration System
1A-28

Gauge
Set 1A-29

Charging Station
IA-29

Leak Testing
the
System
1A-29

Vacuum Pump
1A-30

Availability
of
Refrigerant-12
. . 1A-30

Compressor
Oil 1A-31

Compressor Serial Number
1A-31

Inspection
and
Periodic Service
1A-31

Pre-Delivery Inspection
1A-31

6,000 Mile Inspection
1A-32

Periodic Service
, 1A-32

Installing Gauge
Set to
Check System Operation
....
1A-32

Performance Test
1A-32

Performance Data lA-r33

Comfortron System Operational Test
1A-33

Chevrolet Comfortron Tester
1A-34

Complete System Checks
1A-35

Maintenance
and
Adjustments ......
1A-37

Evaporator Comtrol Valve (POA)
.
1A-37
Page

Thermostatic Switch
1A-37

Expansion Valve
1A-41

Engine Idle Compensator
. . .
1A-42

Evacuating
and
Charging Procedures
1A-42

Purging
the
System
1A-42

Evacuating
and
Charging
the
System
1A-43

Checking
Oil . 1A-43

Component Replacement
and
Minor Repair
1A-45

Refrigerant Line Connections
1A-45

Repair
of
Refrigerant Leaks
1A-46

Preparing System
for
Replacement
of

Component Parts
. 1A-46

Foreign Material
in the
System
.
1A-47

Condenser
.
1A-48

Receiver-Dehydrator
1A-48

Evaporator
1A-49

Expansion Valve
1A-57

Evaporator Control Valve (POA)
1A-59

Thermostatic Switch
or
Blower Switch
. .
1A-59

All Weather-Pull Cable
1A-61

Blower Assembly
1A-62

Air Inlet Valve
.
1A-64

Blower
and
Evaporator Assembly
1A-64

Air Distributor Assembly
and
Outlet Ducts ...... 1A-64

Comfortron Automatic Control Components
1A-66

Collision Procedure lA-70

Four-Season Heater Components
1A-73

Comfortron Heater Components
. . . 1A-75

Compressor
1A-76

Wiring Diagrams
1A-78

Special Tools
.
1A-84

GENERAL DESCRIPTION

Four
air
conditioning systems
are
covered
in
this

section. They are:

1.
The
Four-Season System (Chevrolet, Chevelle,

Camaro and Corvette).

2.
The Comfortron System (Chevrolet).

3.
The All Weather System (Chevy n).

4.
The Universal System (Chevrolet, Chevelle, Chevy
n,

Camaro)

Underhood components (that
is, the
compressor,
con-

denser
and
receiver-dehydrator)
are
much
the
same
in

type,
location
and
method
of
attachment
on all of
the

above systems. The six-cylinder reciprocating compres-

sor
is
bracket-mounted
to the
engine
and
belt driven

from
the
crankshaft pulley.
The
condenser
is
mounted

ahead
of the
engine cooling radiator
and the
receiver-

dehydrator
is
mounted
in
the refrigerant line downstream

of
the
condenser.
All
cooling system components
are

connected by means
of
flexible refrigerant lines.

Evaporator size
and
location differ from system
to

system
as do
methods
of
temperature control
and air

supply
and
distribution.

FOUR-SEASON SYSTEM

The Four-Season system used
in the
Chevrolet,

Chevelle, Camaro,
and
Corvette vehicles
may be
iden-

tified
by the
fact that
it
uses
an
evaporator pressure

control known
as the POA
(Pressure Operated Absolute)

suction throttling valve.
Both
the
heating
and
cooling functions
are
performed

by this system.
Air
entering
the
vehicle must pass

through
the
cooling unit (evaporator)
and
through
(or

around)
the
heating unit,
in
that order, and the system
is

thus referred to
as a
''reheat" system.

The evaporator provides maximum cooling
of the air

passing through
the
core when
the air
conditioning sys-

tem
is
calling
for
cooling.
The
control valve acts in the

system only
to
control
the
evaporator pressure
so
that

minimum possible temperature
is
achieved without core

freeze-up.
The
valve
is
preset,
has no
manual con-

trol,
is
automatically altitude compensated,
and non-

repairable.

The heater core will be hot
at
all times since no water

valve
is
present
in
the system.

System operation
is as
follows (See Figure 24 and 25):

Air, either outside
air or
recirculated
air
enters
the

system
and is
forced through
the
system by the blower.

As
the air
passes through
the
evaporator core,
it

receives maximum cooling
if
the
air
conditioning controls

are calling
for
cooling. After leaving
the
evaporator,

the
air
enters
the
Heater
and Air
Conditioner Selector

Duct Assembly where,
by
means
of
manually operated

diverter doors,
it is
caused
to
pass through
or to
bypass

the heater core
in the
proportions necessary
to
provide

the desired outlet temperature. Conditioned airflow then

enters
the
vehicle through either
the
floor distributor

duct
or the
dash outlets. Remember that the heater core

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-36

(These tests should be performed with the engine at operating temperature.)

SYSTEM CHECKS

Control

Head

Setting

High

Front

Lo

Front

Lo

Front

Hi

Front

Hi

Front
Tester Settings

Function

Manual

Manual

Manual

Manual

De-ice

65° on

Temp.

Dial

Hi

Front

Hi

Front

Hi

Front
Auto-

Matic

1 1

Auto-

matic

Manual

Manual
Manual

Control

Max.

Heat

Rotate

from

Max.

Heat to

Max.

Cold

150

Max.

Cold

Max.

Cold

Max.

Cold

Max.

Heat

Max.

Heat

Max.

Cold
Voltage

Trans-

ducer

Trans-

ducer

Ampli-

fier

Trans-

ducer

Probe

Probe

Trans-

ducer

Trans.
Tester Should

Indicate:

High Blower

Maximum Heat

Reduced Blower

Speed

Complete series of

blower changes from

Hi to Lo to Hi

again.

AMPLIFIE:

Remove conn, from c

Voltage reading she

Short this lead to grc

Voltage reading she

No voltage change in<

COMPRESSOR C

Cooling System

Operation

DE-ICE i

Assuming rest of

system is operating

normally: Max. Heat

1
to windshield.

SENSOR STR

•—

TRAtfSDtfC

0-3"
Vac. Reading

8 Volts Min.

9"
Min.
Vac.
Reading

0-4 Voltage Reading
If not, check

the following:

Fuse in Slock

In Line Fuse

High Blower

Delay Relay

Duct Delay

Thermistor

High Blower

Delay Sensor

Power Servo

Blower Switch

Resistor

Blower Motor

Wiring Harness

Blower Switch

Master Delay

Thermistor

Master Delay

Relay

Resistor

Power Servo

Blower Motor

CHECK

Resistor

I CHECK
Electrical Diagram

Probe Points:

1-2

8-9

10-21

20

18

19

*
9-46

-r

^2-3
15

16

Checked during

above procedure.

(This is a com-

plete step-by-step

high blower circuit

check which also

checks wiring

harness.)

4

5

6

L2-13

L4

""§2-15

39-46

1
16 1

14

22-40-42-44-15

.ontrol head temperature dial.

>uld be 9 volts minimum,

jund.

>uld be 0 volts,

iicates malfunctioning of amplifier.

JUTCJH CHUCK

Compressor Clutch

(Grille Temp, must

be above 40°.)

IRCUIT

Blower Switch

Master Delay

Relay

Transd

NGCl
ucer

Sensor String

2R CHECK

Transducer voltage

&t Max. Cold

position)

Transducer Ground

Hi Blower Outside

air (air door closed

to car body). Hot air

from heater outlets.

Hi Blower Recirc.

Air (air door open

to car body) cold air

from A/C outlets.
24-25-26-27-28
Voltmete

should re
ad

Battery Voltage

Battery Voltage

Battery Voltage

. Vtinimum
6
volts

Battery Voltage

Minimum
6
volts

Battery Vo]

Batterv Vo]
Ltage

Ltage

Battery Voltage

Batterv Voltage

3a

Bai
:terv Vo

tterv Vo
tage

tage

Minimum
6
volts

Batterv Voltage

Minimum
6
volts

Battery Voltage

Minimum
8
volts

Minimum 8 volts

Minimum 8 volts

Batterv Voltage

Minimum 8 volts

1 III • II »ll. —..• —•— . !!•• 1

Battery Voltage

3-23

20-10-21

38

29-30-31-32-33-

34-35-36

37-38

Defective Power Servo; Leak in Vacuum

System; Temp.; Door Link Disconnected

or Jammed; Defective Vacuum Relay

Valve

Defective Mode Door Diaphragm
Batterv Voltage

Battery Voltage

Zero Voltage

Battery Voltage

Battery Voltage

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-38

HIGH BLOWER

DELAY RELAY

O) MASTER AND

HIGH BLOWER

DELAY RELAY

GROUND

Fig.
49A-Comfortron Wiring Diagram-Underhood

CHEVROLET CHASSIS SERVICE AAANUAL

HEATER AND AIR CONDITIONING 1A-39

BROWN

BROWN

LT.
GREEN

BROWN

DK. GREEN

CONTROL

SWITCH

N-CAR
SENSOR

"—ORANGE—(36

[y—LT. GREEN

*)WWWW 55|—jg

TRANSDUCER

POWER SERVO

HIGH BLOWER MASTER FEEDBACK

DELAY DELAY POTENTIOMETER

THERMISTER THERMISTER

Fig.
49B-Comforrron Wiring Diagram-Underdash

CHEVROLET CHASSIS SERVICE AAANUAL

HEATER AND AIR CONDITIONING 1A-78

WIRING DIAGRAMS

Blower

Motor

Resistor
•

Asm

EVAPORATOR—v

ASM.
\

-Diode
(Arc I

suppressor)
^\

16B
—>

-COMPRESSOR

Clutch Coil

•To battery positive

(+) terminal
No vacuum

in hose
#3

Blower

intake

air

Outside

air entry

Valve

by vacuum
in

hose
#3
Valve

normally

closed (spring

held)

Inside

car
air

(Recirc.)
AIR INLET

VALVE

POSITION:

Outside
air
intake

Recirc. air'intake

CONTROL ASM

TEMP CONTROL LEVER

(Operates temp valve

cable
&
equipment
in

chart shown below)
Compressor
Sw.

(Normally closed

Temp valve

begins
to
open

valveV

cable
arm

•Fan Speed Selector Switch

Switch

lever

position

Off

Low

Med

High
Contacts

made

B
to
None

BtoL

B to L
&
M

B to
L
& H
Fan

speed

Low

Low

Med

High
Resistance

in series with

Bio Motor

Hi

Rl

(RiR2)/(Rl+R2)

None

•Blower switch contacts must
be
dosed

before
fan
switch will
be
operable.
COLD
(O.
A.)

COLD a.A.)

Blower

H
y—low
switch

M/
-med
(Norm,

closed

contacts)

Fan speed switch

(See chart
at
left)

To vacuum,

tank

EXTENSION—vy

Horn relay "Bat" WIRE
ASM
X
harness

terminal

V
.**-__.. ;_
1 I panel

Legend:

___. —
Production wiring

Wire
is
part
of
equip.

•—————* Air
conditioning
wrg.
| i

T Agn. sw.

accsy

I term.

I
Temp

Control

Lever

Position

OFF

VENT.

COLD(I.A.)

COLEKO.AJ

HOT
Blower

(Master)

switch

contacts

Open

Closed

Closed

Closed

Closed
Vac switch

connects

vac source

to hose
#

#2

#2
&
#3

None

#3

#2
&
#3
Compressor

switch

contacts:

Open

Open

Closed

Closed

Open
Blower

intake
air

Outside
car air

intake used

Inside
car air

recirculated

Outside
car air

intake used

.Outside
car air

intake used

Fig. 114—Chevrolet—Four-Season Wiring Diagram

CHEVROLET CHASSIS SERVICE MANUAL

HEATER
AND AIR CONDITIONING IA-79

BAT.
CABLE

ASM

A/C
wrg fwd of
dash

exc
bat.
cables,
ext
wire
&

compressor
grd
wire
is
part

of engine wiring harness.

"COMPRESSOR"
SW:

"OFF" POSN

"ON"
POSN
RELAY

ASM

/-DASH

/
PANEL

RESISTOR

ASM

LUTCH

COIL

:OMI

GRD
WIRE
ASM
MPRESSOR

BAT.
TERM

ON START

MTR SOL

EXTENSION WIRE ASM

._
J

J
^-CONTROL
SW

CONTACTS

B TO NONE

BTOL

BTOL&M

BTOL6H

•IGN SW ACCSY TERM.

A/C wrg
to
rear
of
dash

of
inst pnl harness.

Fig.
115—CheveIle—Four-Season Wiring Diagram

CHEVROLET
CHASSIS SERVICE MANUAL

HEATER
AND AIR
CONDITIONING
1A-80

EVAPORATOR ASM.

Blower

Motor
INSIDE VALVE

(Normally closed

-spring held)

PLENUM VALVE

(Normally open

-spring held)
Actuator

(Vacuum

operated)

Inside car air (Recirc*

CONTROL ASM

TEMP CONTROL LEVER

•(Operates temp valve

cable
&
equipment in

hart shown below)

Temp valve

begins to

16DG

Fuse (In-line^

COMPRESSOR

Clutch Coil DASH-

PANEL

•Fan Speed Selector Switch

Switch

lever

position

Off

Low

"HeST

High
Contacts

B to
None

BtoL

B to L b U

BtoL&H
Fan

speed

Low

Low

Med

High
Resistance

in series with

Bio Motor

Rl

Rl

RlR2)/(Rl+R2)

None

•Blower switch contacts must be closed

before fan switch will be operable.

-To battery positive

(-0 terminal

•
Horn relay

terminal"
"Batf
To vacuum

tank

EXTENSION

WIRE
ASM
(Normally closed

contacts-*vac

operated)

7
*- Fan speed switch

(See chart at left)

•/-Wire is

\ part of

I inst panel

harness

Legend:

— Production wiring

————
Wire Is part of equip.

•mmmmmmmmmmmmmm*
AIT
Conditioning
WTg*
Temp

Control

Lever

Position

OFF

VENT

COLD

a.A.)

COLD

(O.A.)

HOT
Blower

(Master)

switch

contacts

Open

Closed

Closed

Closed

Closed
Vac switch

connects

vac source

to hose #

#2
&
#3

#2

#3

None

#2
Compressor

switch

contacts^

Open

Open

Closed

Closed

Open
Blower

intake air

Outside car air

intake used

Inside car air

recir culated

Outside car air

intake used

Outside car air

intake used

Fig.
116—Camaro—Four-Season Wiring Diagram

CHEVROLET CHASSIS SERVICE

HEATER AND AIR CONDITIONING 1A-81

HORN RELAY

r

CONN.-

14 BROWN

(TO FUSE

PANEL)
BATTERY
1

—I ^ COMPR

ESSOR

DASH y

V-^ PANEL \

GROMMET—%
1 \

_ J~ ") "^

>14 BLACK/RED STRIPE-

FUSE .20 AMP.

•WIRE ASM. BLOWER-

MOTOR
14 BLACK 1

IGNITION SWITCH1

(ACCESSORY

TERMINAL)

CONTROL SWITCH
-RESISTOR

CONN.

•14 TAN

•16 BLACK

LIGHT BLUE STRIPE

•THERMOSTAT CONTROL

EVAPORATOR & BLOWER ASM.

Fig.
117—Universal System Wiring Diagram (Typical)

CHEVROLET CHASSI

HEATER AND AIR CONDITIONING 1A-82

•BATTERY

(POS)
CABLE
NOTE
When
control
switch*

is !TOFF"
&
Air
Cond
is
"ON"

(Control
knob
pulled
but) the

blower
fan'will
run at low
speed.
CONTROL
SWITCH

CONNECTIONS

OFF

LOW

MED

HIGH
B
TO
NONE

B
TO L

BTOL&M

B
TO L
&
H

COMPRESSOR
GROUND

WIRE
ASM
BATTERY

(NEGATIVE)

CABLE

COMPRESSOR
ASM

DASHPAJSTEL

GROMMET

16DG
CONTROL

SWITCH

RESISTOR

ASM

14LBL

14BRN
CLUTCH

COIL

EXTENSION

WIRE
ASM
-14BRN--N

JUNC

BLOCKi

OSTATIC

SWITCH

CONTACTS

NORMALLY

CLOSED
STARTING

MOTOR

SOLENOID

BLOWER

MOTOR
AIR
COND

CONTROL

(PUSH-PULL)

KNOB

DOOR
SWITCH

(PUSH
BUTTON

NORMALLY

CLOSED)
RELAY

ASM

HORN

RELAY

DIVERTER

DOOR CABLE

FUSE

PANEL

EVAPORATOR

ASM

IGNITION SWITCH-

ACCESSORY TERMINAL)

Fig. 118—All Weather Wiring Diagram (Chevy II)

CHEVROLET CHASSIS SERVICE MANUAL

HEATER AND AIR CONDITIONING 1A-83

DIVERTER DOOR

CRANK POSITIONS:

AIR COND "ON"

AIR COND "OFF*
AIR COND SWITCH

(PUSH BUTTON,

NORMALLY CLOSED

CONTACTS)

BLOWER MOTOR

CONTACTS

NORMALLY

4D

16

16B/Y

COMPRESSOR

GROUND WIRE

ASM

BAT.
TERMINAL

ON STARTING

MOTOR SOLENOID

' BATTERY

CABLE ASM:

NEGATIVE

POSITIVE—*
- CONTROL SWITCH

SET AT:

•OFF

LOW

MED

HIGH
CONTACTS:

BTOBL

BTOL

BTOM

BT0M6B,

CLUTCH

HOUSING
liOli: WHEN CONTROL

SWITCH IS AT "OFF" &

AIR COND. IS "ON", FAN

WILL RUN AT LOW SPEED.

"AIR COND-PULL"

KNOB (SHOWN IN "ON"

POSITION)

TO REGULATOR

HORN

RELAY
16 BRN-BODY WIRING

HARNESS-837

14BRN

I

^
IA^RN
* IGNITION SWITCH

« 12R ACCESSORY TERMINAL

12R f

AMMETER

LEGEND:

AIR COND WIRING (PART OF

ENGINE WIRING HARNESS)

WIRING IS PART OF EQUIP

REG PRODUCTION WIRING

Fig.
119—Corvette—Four-Season Wiring Diagram

CHEVROLET CHASSIS SERVICE MANUAL