GM Service Manual Online
For 1990-2009 cars only
Table 1: Blue C1 32 Pin Connector End View
Table 2: Red C2 32 Pin Connector End View
Table 3: Clear C3 32 Pin Connector End View
Table 4: Black C4 24 Pin Connector End View

Blue C1 32 Pin Connector End View


Object Number: 358772  Size: CF

Connector Part Information

    • 12129025
    • BLU C1 32 Pin Connector

Pin

Wire Color

Circuit No.

Function

1-2

--

--

Not Used

3

BRN/WHT

633

1X CMP Signal

4-6

--

--

Not Used

7

TAN

1667

HO2S Low Bank 2 Sensor 1

8

PNK/BLK

632

CMP Low

9

PPL

30

Fuel Gage

10-13

--

--

Not Used

14

BRN

436

AIR Relay Control (California Only)

15

YEL/BLK

1827

VSS

16-17

--

--

Not Used

18

PPL/WHT

1589

Dual Tank Fuel Module

19

PPL/WHT

1665

HO2S High Bank 1 Sensor 1

20

PPL/WHT

1668

HO2S High Bank 2 Sensor 2

21

PPL

1666

HO2S High Bank 2 Sensor 1

22

PPL

1670

HO2S High Bank 1 Sensor 3

23

--

--

Not Used

24

TAN/WHT

1669

HO2S Low Bank 2 Sensor 2

25

TAN/WHT

1653

HO2S Low Bank 1 Sensor 1

26

TAN

1671

HO2S Low Bank 1 Sensor 3

27

--

--

Not Used

28

PPL

574

CKP Low

29

LT.GRN/BLK

822

VSS Low

30

PPL/WHT

821

VSS Signal

31

Yel

573

4X CKP Signal

32

--

--

Not Used

Red C2 32 Pin Connector End View


Object Number: 358777  Size: CF

Connector Part Information

    • 12129025
    • RED C2 32 Pin Connector

Pin

Wire Color

Circuit No.

Function

1

--

--

Not Used

2

WHT

1310

Canister Vent Solenoid

3

--

--

Not Used

4

YEL/BLK

1223

2-3 Shift Solenoid

5

--

--

Not Used

6

LT/GRN

1222

1-2 Shift Solenoid

7

BRN

418

PWM TCC Solenoid

8

BLK

1744

Injector # 1 Control

9

DK/BLU/WHT

878

Injector # 8 Control

10

BRN

1456

EGR Pintle Position

11

LT/GRN/BLK

1745

Injector # 2 Control

12

RED/BLK

877

Injector # 7 Control

13

LT/GRN/WHT

1749

IAC B High

14

LT/BLU/WHT

1747

IAC A High

15

BLK/WHT

845

Injector # 5 Control

16

YEL/BLK

846

Injector # 6 Control

17-18

--

--

Not Used

19

DK/BLU

496

KS Signal

20

--

--

Not Used

21

LT/GRN

432

MAP Signal

22

TAN

472

IAT Signal

23

YEL

410

ECT Signal

24

DK/BLU

417

TP Signal

25

DK/GRN

890

Fuel Tank Vacuum Sensor

26

--

--

Not Used

27

YEL/BLK

1227

TFT Signal (Automatic Transmission only)

28

YEL

492

MAF Signal

29

LT/GRN/BLK

444

IAC High

30

LT/BLU/BLK

1748

IAC Low

31

LT/BLU/BLK

844

Injector #4 control

32

PNK/BLK

1746

Injector #3 control

Clear C3 32 Pin Connector End View


Object Number: 358779  Size: CF

Connector Part Information

    • 12129025
    • CLR C3 32 Pin Connector

Pin

Wire Color

Circuit No.

Function

1

DK/GRN/WHT

459

A/C Relay

2

DK/GRN/WHT

--

428

Purge Canister Solenoid

3

--

--

Not Used

4

BLK

452

ECT/TP Sensor Ground

5

--

--

Not Used

6

RED/BLK

1228

PCS High

7

DK/BLU/WHT

1231

Input Speed Sensor Low

8

RED/BLK

1230

Input Speed Sensor High

9

WHT

423

IC Control

10

--

--

Not Used

11

RED

1226

Range Signal C

12

GRY

416

TP Sensor 5V Reference

13

PPL

1589

Fuel Level Sensor Signal

14

DK/BLU

604

A/C Recirculation

15

--

--

Not Used

16

LT/BLU/WHT

1229

PCS Low

17

TAN/WHT

451

VCM Ground

18

BLK/WHT

451

VCM Ground

19

BLK

470

IAT/MAP/EGR Sensor Ground

20

--

--

Not Used

21

ORN

440

Battery positive voltage

22

DK/BLU

1225

Range Signal B

23

PNK

1224

Range Signal A

24

--

--

Not Used

25

DK/GRN/WHT

762

A/C Request Signal

26

--

--

Not Used

27

GRY

474

EGR/MAP 5V Reference

28-29

--

--

Not Used

30

DK/GRN

603

A/C Compressor Cycling Switch

31-32

--

--

Not Used

Black C4 24 Pin Connector End View


Object Number: 358782  Size: CF

Connector Part Information

    • 12129225
    • BLK C4 32 Pin Connector

Pin

Wire Color

Circuit No.

Function

1

DK/GRN/WHT

465

Fuel Pump Relay Control

2

--

--

Not Used

3

DK/GRN/WHT

817

VSS Output Signal (TCCM,Radio,Cruise)

4

DK/GRN

389

VSS Output Signal (speedo)

5

BRN/WHT

419

MIL Control

6

--

--

Not Used

7

DK/GRN

1614

Inlet Air Actuator

8-9

--

--

Not Used

10

PPL

420

Brake Signal

11

PPL

1807

Class 2 Serial Data

12

BLK

900

Dual Fuel Module Return

13

BRN

441

Ignition positive voltage

14-15

--

--

Not Used

16

RED

1676

EGR Valve Feed

17

--

--

Not Used

18

PNK

439

Ignition positive voltage

19

--

--

Not Used

20

WHT

257

EGR Valve Control

21-23

--

--

Not Used

24

LT/BLU/BLK

396

Cruise Engaged Signal