GM Service Manual Online
For 1990-2009 cars only
Table 1: Engine Control Module (ECM) - C1
Table 2: Engine Control Module (ECM) - C2

Engine Control Module (ECM) - C1


Object Number: 655733  Size: CH

Connector Part Information

    • 12191489
    • 80-Way F Micro-Pack 100W Sealed (BLU)

Pin

Wire Color

Circuit No.

Function

1

BLK/WHT

451

Ground

2

LT GRN

1867

12 Volt Reference

3

BLK

1744

Fuel Injector 1 Control

4

LT BLU /BLK

844

Fuel Injector 4 Control

5

TAN/WHT

332

Oil Pressure Sensor Signal

6

BRN

1456

EGR Vacuum Sensor Signal - w/California Emissions Only

7

YEL/BLK

975

5 Volt Reference

8

GRY

2705

5 Volt Reference

9

DK GRN

2362

SAE J1939 Serial Data Bus -

10

YEL

2361

SAE J1939 Serial Data Bus+

11

--

--

Not Used

12

LT BLU/WHT

1869

CKP Sensor Signal

13 - 16

--

--

Not Used

17

YEL/BLK

508

Water In Fuel Indicator Control

18

DK BLU

84

Cruise Control Set/Coast Switch Signal

19

PNK

439

Ignition 1 Voltage

20

ORN

440

Battery Positive Voltage

21

YEL/BLK

1868

Low Reference

22

GRY/BLK

87

Cruise Control Resume/Accel Switch Signal

23-24

--

--

Not Used

25

ORN/BLK

469

Low Reference

26 -28

--

--

Not Used

29

TAN

986

Intake Heater Diag 1

30

LT GRN

1478

Coolant Level Switch Signal

31

--

--

Not Used

32

BRN

2524

Generator 2 Turn On Signal

33

PPL

806

Crank Voltage

34

ORN/BLK

1786

Park/Neutral Signal

35

GRY

48

CPP Switch Signal

36

LT GRN/BLK

1745

Fuel Injector 2 Control

37

BLU/WHT

845

Fuel Injector 5 Control

38 -39

--

--

Not Used

40

BLK/WHT

451

Ground

41

BRN

971

Low Reference

42

--

--

Not Used

43

DK BLU/WHT

878

Fuel Injector 8 Control

44

PNK/BLK

1746

Fuel Injector 3 Control

45

TAN

1274

5 Volt Reference

46

WHT/BLK

2932

5 Volt Reference

47

WHT/BLK

1164

5 Volt Reference

48

TAN

2917

5 Volt Reference

49 -51

--

--

Not Used

52

LT BLU

506

Glow Plug Signal

53

--

--

Not Used

54

PPL

1272

Low Reference

55

LT BLU

1162

APP Sensor 2 Signal

56

--

--

Not Used

57

ORN

440

Battery Positive Voltage

58

DK GRN

1049

Class 2 Serial Data

59

YEL

710

Class 2 Serial Data

60

--

--

Not Used

61

PNK/BLK

632

Low Reference

62

LT GRN

1324

Backup Lamp Supply Voltage

63

--

--

Not Used

64

BLK

552

Low Reference

65

GRY

1273

Low Reference

66 -69

--

--

Not Used

70

BRN

1174

Oil Level Switch Signal

71

LT GRN

488

PTO Enable

72

--

--

Not Used

73

BRN/WHT

633

CMP Sensor Signal

74

YEL

410

ECT Sensor Signal

75

PNK

1020

Off/Run/Crank Voltage

76

YEL/BLK

846

Fuel Injector 6 Control

77

RED/BLK

877

Fuel Injector 7 Control

78

PPL

985

IA Heater Relay Control

79

GRY/BLK

2219

FICM Relay Control

80

GRY

720

Low Reference

Engine Control Module (ECM) - C2


Object Number: 684875  Size: CH

Connector Part Information

    • 12191488
    • 80-Way F Micro-Pack 100W Sealed (CLR)

Pin

Wire Color

Circuit No.

Function

1

BLK/WHT

451

Ground

2

WHT

257

EGR Valve Vacuum Solenoid Control - w/California Emissions Only

3-5

--

--

Not Used

6

YEL

505

Glow Plug Relay Control

7 -8

--

--

Not Used

9

DK GRN /WHT

465

Fuel Pump Relay Control

10

WHT

121

Engine Speed Signal

11

DK BLU

604

A/C High Pressure Recirculation Switch Signal

12

DK GRN

1163

APP Sensor 3 Signal

13

YEL

2522

PTO Feedback Status

14

LT GRN

432

Boost Sensor Signal

15

BRN

25

Charge Indicator Control

16

GRY

397

Cruise Control On Switch Signal

17

DK GRN/WHT

2523

A/C Request Signal

18

LT BLU

1320

CHMSL Supply Voltage

19

BLK/WHT

1695

Axle Switch Signal

20

LT GRN/BLK

822

VSS Low Signal (Except Allison

21

PPL/WHT

821

VSS High Signal (except Allison)

YEL

400

Signal High - Front - Allison Transmission

22

--

--

Not Used

23

ORN/BLK

2919

Low Reference

24

DK BLU

1161

APP Sensor 1 Signal

25

YEL

1578

Fuel Temperature Signal

26 -28

--

--

Not Used

29

GRY

597

5 Volt Reference

30 -32

--

--

Not Used

33

DK GRN

1614

Recirculation Door Control

34

DK GRN/WHT

459

A/C Compressor Clutch Relay Control

35

PNK/WHT

1101

Damping Lift/Dive Signal

36

DK BLU

507

Wait to Start Indicator Control

37

PPL

2562

PTO Engage Signal

38

--

--

Not Used

39

RED

631

12 Volt Reference

40

BLK/WHT

451

Ground

41

GRY/BLK

2931

Low Reference

42

PPL/WHT

2530

Fuel Pressure Regulator Solenoid Supply Voltage

43

--

--

Not Used

44

PNK

1039

Ignition 1 Voltage

45

--

--

Not Used

46

BRN/WHT

419

MIL Control

47

DK GRN/WHT

428

EGR Throttle Valve Vacuum Solenoid Control - w/California Emissions Only

48

WHT

1310

EGR Vacuum Vent Solenoid Control - w/California Emissions Only

49

YEL/BLK

1827

Vehicle Speed Signal

50

DK GRN/WHT

817

Vehicle Speed Signal

51

TAN

472

IAT Sensor Signal

52

GRY

23

Generator Field Duty Cycle Signal

53

DK BLU

2687

TCM MIL Request

54

PPL/WHT

1589

Fuel Level Sensor Signal - Primary

55

DK GRN

603

A/C Low Pressure Switch Signal

56

LT BLU

494

PTO Engine Disable

57

BLK

470

Low Reference

58

YEL

2918

FRP Sensor Signal

59

PPL

420

TCC Brake Switch/Cruise Control Release Signal

60

BRN

718

Low Reference

61

--

--

Not Used

62

TAN

986

Intake Heater Diag 2

63

GRY/BLK

1694

4WD Low Signal

64

GRY/BLK

433

Baro Sensor Signal

65

YEL

492

MAF Sensor Signal

66 -72

--

--

Not Used

73

DK BLU

1936

Fuel Level Sensor Signal - Secondary

74-75

--

--

Not Used

76

LT BLU

2832

Engine Speed Signal

77

YEL

2834

Fuel Pressure Regulator Solenoid Control

78

ORN/BLK

1057

Low Reference

79 -80

--

--

Not Used