GM Service Manual Online
For 1990-2009 cars only
Table 1: Vehicle Control Module (VCM) Connector C1
Table 2: Vehicle Control Module (VCM) Connector C2
Table 3: Vehicle Control Module (VCM) Connector C3
Table 4: Vehicle Control Module (VCM) Connector C4

Vehicle Control Module (VCM) Connector C1


Object Number: 20329  Size: CF

Connector Part Information

    • 12129025
    • 32 - Way F Micro - Pack 100 Series (Blue)

Pin

Wire Color

Circuit No.

Function

Component Connector Cavity

DTC(s) Affected

Possible Symptoms From a Faulty Circuit

1

--

--

Not Used

--

--

--

2

--

--

Not Used

A

--

--

3

BRN/WHT

633

1x Camshaft Position signal

B

P0340 P0341

--

4

PNK

539

Ignition Feed

--

--

--

5

YEL/BLK

846

Injector 6 Control

--

P0306

Rough Idle, Loss of Power

6

--

--

Not Used

--

--

--

7

TAN

1667

HO2S Low Right Bank (Bank 2 Sensor 1)

A

P0152

--

8

PNK/BLK

632

Camshaft Position Sensor Low

A

P0340 P0341

--

9

--

--

Not Used

--

--

--

10

TAN/BLK

422

TCC Enable

T

--

No TCC

11

--

--

Not Used

--

--

--

12

DK GRN/WHT

428

EVAP Purge Solenoid Control

A

P0440 P0441

Purge Inop

13

WHT

687

3-2 Down Shift Solenoid

S

--

Incorrect Gear State

14

--

--

Not Used

--

--

--

15

YEL/BLK

1827

VSS Output

--

--

--

16

--

--

Not Used

--

--

--

17

--

--

Not Used

--

--

--

18

GRY

435

EGR Low

A

P0401 P1406

EGR Inop

19

PPL/WHT

1665

HO2S High Left Bank (Bank 1 Sensor 1)

B

P0131

--

20

PPL

1670

HO2S High Pre-Catalyst (Bank 1 Sensor 2)

B

P0137

--

21

PPL

1666

HO2S High Right Bank (Bank 2 Sensor 1)

B

P0151

--

22

PPL/WHT

1668

HO2S High Post Catalyst (Bank 1 Sensor 3)

B

P0143

--

23

--

--

Not Used

--

--

--

24

TAN/WHT

1671

HO2S Low Pre-Catalyst (Bank 1 Sensor 2)

A

P0138

--

25

TAN

1653

HO2S Low Left Bank (Bank 1 Sensor 1)

A

P0132

--

26

TAN/WHT

1669

HO2S Low Post Catalyst (Bank 1 Sensor 3)

A

P0144

--

27

--

--

Not Used

--

--

--

28

PPL

574

Crankshaft Position Sensor Low

B

P0336 P0338 P0339

No Start

29

LT GRN/BLK

822

VSS Low

A

--

--

30

PPL/WHT

821

VSS High

B

--

--

31

YEL

573

3x Crankshaft Position Signal

A

P0337 P0338 P0339

No Start

32

--

--

Not Used

--

--

--

Vehicle Control Module (VCM) Connector C2


Object Number: 20329  Size: CF

Connector Part Information

    • 12129025
    • 32 - Way F Micro -Pack 100 Series (Red)

Pin

Wire Color

Circuit No.

Function

Component Connector Cavity

DTC(s) Affected

Possible Symptoms From a Faulty Circuit

1

--

--

Not Used

--

--

--

2

WHT

1310

EVAP Canister Vent Solenoid

--

--

--

3

BLK

1744

Injector 1 Control

A

P0301

Rough Idle

4

YEL/BLK

1223

2-3 Solenoid

B

--

Incorrect Gear State

5

--

--

Not Used

--

--

--

6

LT GRN

1222

1-2 Solenoid

A

--

Incorrect Gear State

7

BRN

418

TCC PWM

U

--

TCC Inop

8

--

--

Not Used

--

--

--

9

DK GRN/WHT

459

A/C Relay Enable

C1

--

A/C Inop

10

BRN

1456

EGR Pintle Position Signal

C

1406

EGR Inop

11

--

--

Not Used

--

--

--

12

--

--

Not Used

--

--

--

13

LT GRN/WHT

1749

IAC B High

B

P0507 P0508 P1508 P1509

Incorrect Idle Speed

14

LT BLU/WHT

1747

IAC A High

D

P0507 P0508 P1508 P1509

Incorrect Idle Speed

15

LT GRN/BLK

1745

Injector 2 Control

N

P0302

Rough Idle

16

PNK/BLK

1746

Injector 3 Control

--

P0303

Rough Idle

17

--

--

Not Used

--

--

--

18

--

--

Not Used

--

--

--

19

DK BLU

496

KS Signal

--

P0325 P0327

Poor Performance

20

--

--

Not Used

--

--

--

21

LT GRN

432

MAP Signal

B

P0106 P0107 P0108 P1107

Poor Performance

22

TAN

472

IAT Signal

A

P0112 P0113 P1111 P1112

Poor Performance

23

YEL

410

ECT Signal

A

P0117 P0118 P1114 P1115

Poor Performance

24

DK BLU

417

TP Signal

C

P0121 P0122 P0123 P1121 P1122

Poor Performance

Harsh Shifts

25

DK GRN

890

Fuel Tank Vacuum Sensor

--

--

--

26

--

--

Not Used

--

--

--

27

YEL/BLK

1227

TFT Signal

L

--

Early TCC

28

YEL

492

MAFSignal

A

P0101 P0102 P0103

Poor Performance

29

LT GRN/BLK

444

IAC B Low

A

P0507 P0508 P1508 P1509

Incorrect Idle Speed

30

LT BLU/BLK

1748

IAC A Low

C

P0507 P0508 P1508 P1509

Incorrect Idle Speed

31

BLK/WHT

845

Injector 5 Control

E

P0305

Rough Idle

32

LT BLU/BLK

844

Injector 4 Control

D

P0304

Rough Idle

Vehicle Control Module (VCM) Connector C3


Object Number: 20329  Size: CF

Connector Part Information

    • 12129025
    • 32 - Way F Micro - Pack 100 Series (Gray)

Pin

Wire Color

Circuit No.

Function

Component Connector Cavity

DTC(s) Affected

Possible Symptoms From a Faulty Circuit

1

--

--

Not Used

--

--

--

2

--

--

Not Used

--

--

--

3

--

--

Not Used

--

--

--

4

BLK

452

ECT/TP Sensor Ground

B

--

High Idle

5

--

--

Not Used

--

--

--

6

RED/BLK

1228

PCS High

C

--

Poor Shift Quality

7

--

--

Not Used

--

--

--

8

--

--

Not Used

--

--

--

9

WHT

423

IC Control

B

P1351 P1361

No Start

10

--

--

Not Used

--

--

--

11

RED

1226

Range Signal C

P

--

Erratic Manual Downshifts

12

GRY

416

TP Sensor 5V Reference

A

P0121 P0122 P0123 P1121 P1122

Lack of Power

Harsh Shifts

13

--

--

Not Used

--

--

--

14

--

--

Not Used

--

--

--

15

--

--

Not Used

--

--

--

16

BLU/WHT

1229

PCS Low

D

--

Poor Shift Quality

17

BLK/WHT

551

Ground

--

--

Poor Performance

18

TAN/WHT

451

Ground

--

--

Poor Performance

19

BLK

470

IAT/MAP/EGR/ TFT Ground

--

--

Idle Surge

Exhaust Odor

20

--

--

Not Used

--

--

--

21

ORN

440

Battery Feed

--

--

--

22

DK BLU

1225

Range Signal B

R

--

Erratic Manual Downshifts

23

PNK

1224

Range Signal A

N

--

Erratic Manual Downshifts

24

--

--

Not Used

--

--

--

25

DK GRN/WHT

762

A/C Request (HI)

--

--

A/C Inop

26

--

--

Not Used

--

--

--

27

GRY

474

EGR/MAP Reference

--

--

Poor Performance

Rough Idle

28

--

--

Not Used

--

--

--

29

--

--

Not Used

--

--

--

30

DK BLU

214

A/C Request (LO)

--

--

--

31

--

--

Not Used

--

--

--

32

--

--

Not Used

--

--

--

Vehicle Control Module (VCM) Connector C4


Object Number: 20305  Size: CF

Connector Part Information

    • 12129225
    • 24 - Way F Micro -Pack 100 Series (Black)

Pin

Wire Color

Circuit No.

Function

Component Connector Cavity

DTC(s) Affected

Possible Symptoms From a Faulty Circuit

1

DK GRN/WHT

465

Fuel Pump Relay Control

2

--

Extended Crank When Cold

2

--

--

Not Used

--

--

--

3

DK GRN/WHT

817

VSS Output (Cruise Module)

--

--

--

4

DK GRN

389

VSS Output (i/P)

--

--

Speedometer Inop

5

BRN/WHT

419

MIL Control

24

--

MIL Inop Or Remains On

6

--

--

Not Used

--

--

--

7

--

--

Not Used

--

--

--

8

--

--

Not Used

--

--

--

9

--

--

Not Used

--

--

--

10

PPL

420

Brake Signal

--

--

No TCC

11

PPL

1807

Serial Data

2

--

No Serial Data

12

BLK/WHT

533

Fuel Level Module Return

--

--

--

13

BRN

441

Ignition Feed

--

--

--

14

PPL/WHT

1589

Fuel Level Return

--

--

--

15

--

--

Not Used

--

--

--

16

--

--

Not Used

--

--

--

17

--

--

Not Used

--

--

--

18

PNK

439

Ignition Feed

--

--

No Start

19

--

--

Not Used

--

--

--

20

--

--

Not Used

--

--

--

21

--

--

Not Used

--

--

--

22

--

--

Not Used

--

--

--

23

--

Not Used

--

--

--

24

LT BLU/BLK

396

Cruise Signal

--

--

--