GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2004 🢒 TopKick C-Series (Conventional) C4/C5 🢒 HVAC 🢒 HVAC Systems - Manual 🢒 HVAC Connector End Views
Table 1: A/C Compressor Clutch (C4/C5)
Table 2: A/C Compressor Clutch (C6/C7/C8)
Table 3: A/C Compressor Clutch Relay
Table 4: A/C High Pressure Switch
Table 5: A/C Low Pressure Switch
Table 6: Air Temperature Actuator
Table 7: Blower Motor
Table 8: Blower Motor - Auxiliary C1
Table 9: Blower Motor - Auxiliary C2
Table 10: Blower Motor Relay - Auxiliary
Table 11: Blower Motor Resistor Assembly
Table 12: Blower Motor Resistor - Auxiliary
Table 13: Coolant Bypass Valve Solenoid (Crew Cab)
Table 14: HVAC Control Assembly - Auxiliary
Table 15: HVAC Control Assembly - C1
Table 16: HVAC Control Assembly - C2
Table 17: HVAC Control Assembly - C3
Table 18: Vacuum Pump (Diesel)

A/C Compressor Clutch (C4/C5)


Object Number: 684852 Size: CH

Connector Part Information
    • 12162017
    • 2-Way F Metri-Pack 150 Series Sealed (GY)

Pin

Wire Color

Circuit No.

Function

A

BK

250

Ground

B

D-GN

59

A/C Compressor Clutch Supply Voltage

A/C Compressor Clutch (C6/C7/C8)


Object Number: 684795 Size: CH

Connector Part Information
    • 12052643
    • 2-Way F Metri-Pack 150 Series Sealed (RD)

Pin

Wire Color

Circuit No.

Function

A

BK

250

Ground

B

D-GN

59

A/C Compressor Clutch Supply Voltage

A/C Compressor Clutch Relay


Object Number: 535912 Size: CH

Connector Part Information
    • 12129716
    • 4-Way F Metri-Pack 280 Series Flexlock (GY)

Pin

Wire Color

Circuit No.

Function

30

OG

1240

Battery Positive Voltage

85

D-GN

603

Low Coolant Indicator Control (LG4/LG5)

D-GN/WH

459

A/C Compressor Clutch Relay Control (LB7/L18/LLY)

86

D-GN/WH

459

A/C Compressor Clutch Relay Control (LG4/LG5)

BN

441

Ignition 3 Voltage (L18/LB7/LLY)

87

D-GN

59

A/C Compressor Clutch Supply Voltage

A/C High Pressure Switch


Object Number: 38560 Size: CH

Connector Part Information
    • 12162443
    • 2-Way F (BK)

Pin

Wire Color

Circuit No.

Function

A

D-GN/WH

762

A/C Request Signal (L18/LB7/LLY)

L-GN

66

A/C Request Signal (LG4/LG5)

B

L-GN

66

A/C Request Signal (L18/LB7/LLY)

D-GN/WH

459

A/C Compressor Clutch Relay Control (LG4/LG5)

A/C Low Pressure Switch


Object Number: 537107 Size: CH

Connector Part Information
    • 12052644
    • 2-Way F Metri-Pack 150 Series Sealed (GY)

Pin

Wire Color

Circuit No.

Function

A

BK

250

Ground (L18/LB7/LLY)

D-GN

603

Low Coolant Indicator Control (LG4/LG5)

B

D-GN

603

Low Coolant Indicator Control (L18/LB7/LLY)

BK

250

Ground (LG4/LG5)

Air Temperature Actuator


Object Number: 281207 Size: CH

Connector Part Information
    • 12040953
    • 6-Way F Micro-Pack 100 Series (BK)

Pin

Wire Color

Circuit No.

Function

5-6

--

--

Not Used

7

BK

450

Ground

8

L-BU

733

Left Air Temperature Door Control

9

--

--

Not Used

10

BN

141

Ignition 3 Voltage 7

Blower Motor


Object Number: 62488 Size: CH

Connector Part Information
    • 12084957
    • 2-Way F Metri-Pack 280 Series (BK)

Pin

Wire Color

Circuit No.

Function

A

PU

--

Blower Motor Supply Voltage

B

BK

--

Ground

Blower Motor - Auxiliary C1


Object Number: 874943 Size: CH

Connector Part Information
    • 12040673
    • 1-Way F (BK)

Pin

Wire Color

Circuit No.

Function

A

YE

1172

Auxiliary Blower Motor Supply Voltage

Blower Motor - Auxiliary C2


Object Number: 35348 Size: CH

Connector Part Information
    • 12004267
    • 1-Way F 56 Series Lock Type (BK)

Pin

Wire Color

Circuit No.

Function

A

BK

550

Ground and C36

Blower Motor Relay - Auxiliary


Object Number: 535912 Size: CH

Connector Part Information
    • 12129716
    • 4-Way F Metri-Pack 280 Series Flexlock (GY)

Pin

Wire Color

Circuit No.

Function

30

OG

540

Battery Positive Voltage and C36

85

BK

550

Ground and C36

86

BN

141

Ignition 3 Voltage and C36

87

OG

1923

Auxiliary HVAC Switch Supply Voltage

Blower Motor Resistor Assembly


Object Number: 535914 Size: CH

Connector Part Information
    • 12160746
    • 6-Way F Metri-Pack 280 Series Flexlock Sealed (L-GY)

Pin

Wire Color

Circuit No.

Function

A

RD

542

Battery Positive Voltage

B

OG

52

High Blower Motor Control

C

BK

450

Ground

D

TN

63

Auxiliary Blower Motor Medium Speed Control

E

YE

60

Low Blower Motor Control

F

L-BU

72

Medium 2 Blower Motor Control

Blower Motor Resistor - Auxiliary


Object Number: 284534 Size: CH

Connector Part Information
    • 12077384
    • 3-Way F 56 Series (BK)

Pin

Wire Color

Circuit No.

Function

A

RD

1925

Auxiliary Blower Motor Medium Speed Control

B

YE

1172

Auxiliary Blower Motor Supply Voltage

WH

1924

Auxiliary Blower Motor High Control

C

D-BU

1926

Auxiliary Blower Motor Low Speed Control

Coolant Bypass Valve Solenoid (Crew Cab)


Object Number: 635009 Size: CH

Connector Part Information
    • 12052641
    • 2-Way F Metri-Pack 150 Series (BK)

Pin

Wire Color

Circuit No.

Function

A

GY/BK

1596

Heater Water Control Solenoid Control

B

BK

550

Ground

HVAC Control Assembly - Auxiliary


Object Number: 284533 Size: CH

Connector Part Information
    • 12162066
    • 8-Way F Metri-Pack 280 Series (GY)

Pin

Wire Color

Circuit No.

Function

A

WH

1924

Auxiliary Blower Motor High Speed Control

B

RD

1925

Auxiliary Blower Motor Medium Speed Control

C

GY/BK

1596

Heater Water Control Solenoid Control

D

--

--

Not Used

E

BK

550

Ground

F

D-BU

1926

Auxiliary Blower Motor Low Speed Control

G

OG

1923

Auxiliary HVAC Switch Supply Voltage

H

GY

8

Instrument Panel Lamp Supply Voltage 1

HVAC Control Assembly - C1


Object Number: 68737 Size: CH

Connector Part Information
    • 12129489
    • 3-Way F Metri-Pack 280 Series Flexlock (BK)

Pin

Wire Color

Circuit No.

Function

A

WH

119

Mode Door Control

B

BK

450

Ground

C

GY

8

Instrument Panel Lamp Supply Voltage 1

HVAC Control Assembly - C2


Object Number: 62469 Size: CH

Connector Part Information
    • 12064998
    • 8-Way F Metri-Pack 280 Series (BK)

Pin

Wire Color

Circuit No.

Function

A

YE

60

Low Blower Motor Control

B

TN

63

Auxiliary Blower Motor Medium Speed Control 5

C

L-BU

72

Medium 2 Blower Motor Control

D

OG

52

High Blower Motor Control

E

BN

141

Ignition 3 Voltage

F

L-BU

733

Left Air Temperature Door Control

G

WH

119

Mode Door Control

H

L-GN

66

A/C Request Signal w/CJ3

HVAC Control Assembly - C3


Object Number: 62450 Size: CH

Connector Part Information
    • 12052856
    • 4-Way F Metri-Pack 280 Series (BK)

Pin

Wire Color

Circuit No.

Function

A

PU

1093

Rear Defog Element Supply Voltage

B

BN

141

Ignition 3 Voltage

C

BK

450

Ground

D

PU

293

Rear Defog Element Supply

Vacuum Pump (Diesel)


Object Number: 635009 Size: CH

Connector Part Information
    • 12052641
    • 2-Way F Metri-Pack 150 Series (BK)

Pin

Wire Color

Circuit No.

Function

A

BK

350

Battery Positive Voltage

B

BN

141

Ignition 3 Voltage