GM Service Manual Online
For 1990-2009 cars only
Connector 1: Engine Control Module (ECM) C1
Connector 2: Engine Control Module (ECM) C2
Connector 3: Engine Control Module (ECM) C3

Engine Control Module (ECM) C1


Object Number: 784851  Size: CH

Connector Part Information

  • OEM: 15418474
  • Service: 88953346
  • Description: 56-Way Micro 64 Series (BU)

Terminal Part Information

  • Pins: 1, 2, 5, 7, 10, 11, 13, 14, 15, 16, 17, 18, 19, 20, 21, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 35, 36, 37, 42, 43, 45, 46, 49, 51, 53, 54, 55
  • Terminal/Tray: 15359541/4
  • Core/Insulation Crimp: M/M
  • Release Tool/Test Probe: 15381651-2/J-35616-64B (L-BU)

Engine Control Module (ECM) C1

Pin

Wire Color

Circuit No.

Function

1

TN/BK

2500

High Speed GMLAN Serial Data Bus+

2

TN

2501

High Speed GMLAN Serial Data Bus-

3-4

--

--

Not Used

5

TN

1274

5-Volt Reference

6

--

--

Not Used

7

WH/BK

1164

5-Volt Reference

8-9

--

--

Not Used

10

WH

1310

EVAP Canister Vent Solenoid Control

11

OG/BK

380

A/C Refrigerant Pressure Sensor Signal

12

--

--

Not Used

13

OG

5371

Stop Lamp Switch Signal

14

YE

447

Starter Relay Coil Control

15

PU

1807

Class 2 Serial Data (Primary)

16

PU

1807

Class 2 Serial Data (Primary)

17

PK/BK

5290

Ignition 1 Voltage

18

PK

239

Ignition 1 Voltage

19

PK

239

Ignition 1 Voltage

20

RD/WH

1440

Battery Positive Voltage

21

L-BU

1162

APP Sensor 2 Signal

22

--

--

Not Used

23

D-GN/WH

465

Fuel Pump Relay Control - Primary

24

BN/WH

419

MIL Control

25

D-GN/WH

459

A/C Compressor Clutch Relay Control

26

WH

121

Engine Speed Signal

27

D-BU

1161

APP Sensor 1 Signal

28

BN

818

Vehicle Speed Signal

29

YE

492

MAF Sensor Signal

30

PK/WH

1101

Damping Lift/Dive Signal (F55)

31

TN

2760

Low Reference

32

TN

470

Low Reference

33

OG/WH

812

12-Volt Reference or I/P Dimming Voltage Reference

34

--

--

Not Used

35

GY

2700

5-Volt Reference

36

BN

1271

Low Reference

37

PU

1272

Low Reference

38-41

--

--

Not Used

42

D-BU

473

High Speed Cooling Fan Relay Control

43

BN

5069

Main Relay Control

44

--

--

Not Used

45

GY

847

Extended Travel Brake Switch Signal

46

YE

343

Accessory Voltage

47-48

--

--

Not Used

49

YE/BK

5270

Traction Control Data Signal

50

--

--

Not Used

51

TN

472

IAT Sensor Signal

52

--

--

Not Used

53

GY

1884

Cruise Control Set/Coast and Resume/Accelerate Switch Signal

54

YE

5

Crank Voltage

55

D-GN

335

Low Speed Cooling Fan Relay Control

56

--

--

Not Used

Engine Control Module (ECM) C2


Object Number: 784850  Size: CH

Connector Part Information

  • OEM: 15418475
  • Service: 88953274
  • Description: 73-Way F Micro 64 Series (BK)

Terminal Part Information

  • Pins: 3, 4, 8, 10, 11, 12, 13, 14, 17, 18, 19, 20, 21, 22, 23, 24, 25, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 54, 55, 58, 59, 60, 61, 62, 63, 64, 65, 68, 69, 71
  • Terminal/Tray: 15359541/4
  • Core/Insulation Crimp: M/M
  • Release Tool/Test Probe: 15381651-2/J-35616-64B (L-BU)
  • Pins: 73
  • Terminal/Tray: 15304720/19
  • Core/Insulation Crimp: 4/5
  • Release Tool/Test Probe: 15315247/J-35616-4A (PU)

Engine Control Module (ECM) C2

Pin

Wire Color

Circuit No.

Function

1-2

--

--

Not Used

3

D-GN

485

TP Sensor 1 Signal

4

PU

486

TP Sensor 2 Signal

5-7

--

--

Not Used

8

L-GN

432

MAP Sensor Signal

9

--

--

Not Used

10

YE

573

CKP Sensor 1 Signal

11

L-BU

1876

Knock Sensor 2 Signal

12

GY

23

Generator Field Duty Cycle Signal

13

GY

1716

Low Reference

14

L-GN

5282

CMP Actuator Solenoid Control Exhaust Bank 1

15-16

--

--

Not Used

17

TN

1744

Fuel Injector 1 Control

18

OG/BK

1745

Fuel Injector 2 Control

19

D-BU

496

Knock Sensor 1 Signal

20

L-BU/BK

1746

Fuel Injector 3 Control

21

OG/BK

877

Fuel Injector 7 Control

22

L-GN/BK

845

Fuel Injector 5 Control

23

YE/BK

846

Fuel Injector 6 Control

24

D-BU/WH

878

Fuel Injector 8 Control

25

D-GN

5273

CMP Sensor Signal Exhaust Bank 1

26

--

--

Not Used

27

BN/WH

5303

Low Reference

28

GY

2303

Low Reference

29

PU

5284

CMP Actuator Solenoid Control Intake Bank 1

30

YE/BK

844

Fuel Injector 4 Control

31

OG/BK

5272

CMP Actuator Solenoid Control Intake Bank 2

32

OG

5275

CMP Sensor Signal Intake Bank 1

33

D-BU

5300

12-Volt Reference

34

WH/BK

5283

CMP Actuator Solenoid Control Exhaust Bank 2

35

TN

5301

Low Reference

36

OG/BK

469

Low Reference

37

TN

2752

Low Reference

38

TN

2761

Low Reference

39

BN/WH

2130

Low Reference

40

L-BU

5302

12-Volt Reference

41

PU

574

Low Reference

42

BN

2129

Low Reference

43

PU

5274

CMP Sensor Signal Exhaust Bank 2

44

TN

582

TAC Motor Control - 2

45

GY

5296

Low Reference

46

L-GN

5298

12-Volt Reference

47

BN

5299

Low Reference

48

YE

581

TAC Motor Control - 1

49

YE

5276

CMP Sensor Signal Intake Bank 2

50

L-GN

1867

12-Volt Reference

51

GY

2701

5-Volt Reference

52-53

--

--

Not Used

54

YE

410

ECT Sensor Signal

55

D-GN/WH

428

EVAP Canister Purge Solenoid Control

56-57

--

--

Not Used

58

PU

2121

IC 1 Control

59

OG/WH

2122

IC 2 Control

60

OG

2127

IC 7 Control

61

L-BU

2123

IC 3 Control

62

D-GN/WH

2124

IC 4 Control

63

PU/WH

2128

IC 8 Control

64

D-GN

2125

IC 5 Control

65

GY

2704

5-Volt Reference

66-67

--

--

Not Used

68

OG

225

Generator Turn On Signal

69

L-BU/WH

2126

IC 6 Control

70

--

--

Not Used

71

YE/BK

5297

12-Volt Reference

72

--

--

Not Used

73

BK/WH

1551

Ground

Engine Control Module (ECM) C3


Object Number: 1283894  Size: CH

Connector Part Information

  • OEM: 15418476
  • Service: 88953347
  • Description: 56-Way F Micro 64 Series (GY)

Terminal Part Information

  • Pins: 1, 2, 3, 12, 13, 14, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 37, 38, 40, 41, 42, 43, 44, 45, 46, 48, 49, 51
  • Terminal/Tray: 15359541/4
  • Core/Insulation Crimp: M/M
  • Release Tool/Test Probe: 15381651-2/J-35616-64B (L-BU)

Engine Control Module (ECM) C3

Pin

Wire Color

Circuit No.

Function

1

PU

1666

HO2S High Signal - Bank 2 Sensor 1

2

TN

1667

HO2S Low Signal - Bank 2 Sensor 1

3

PU/WH

5281

HO2S Output Pump Current Bank 1 Sensor 1

4-11

--

--

Not Used

12

D-BU

1936

Fuel Level Sensor Signal - Secondary

13

YE

5036

HO2S Heater Low Control - Bank 1 Sensor 2

14

OG/BK

463

Requested Torque Signal

15

--

--

Not Used

16

PU

5035

HO2S Heater Low Control - Bank 2 Sensor 2

17

TN/BK

464

Delivered Torque Signal

18

OG/BK

1786

Ignition Lock Cylinder Control Actuator Signal

19

TN

1671

HO2S Low Signal - Bank 2 Sensor 2

20

PU/WH

1668

HO2S High Signal - Bank 2 Sensor 2

21

TN/WH

1669

HO2S Low Signal - Bank 2 Sensor 2

22

OG

5280

HO2S Input Pump Current Bank 1 Sensor 1

23

BN

1174

Oil Level Switch Signal

24

L-BU

1937

Fuel Gage Sensor - Signal - Right

25

TN/WH

331

Oil Pressure Sensor Signal

26-36

--

--

Not Used

37

TN

452

Low Reference

38

BK

2755

Low Reference

39

--

--

Not Used

40

PU/WH

5037

HO2S Heater Low Control - Bank 1 Sensor 1

41

L-BU

5038

HO2S Heater Low Control - Bank 2 Sensor 1

42

GY

2709

5-Volt Reference

43

PU

1670

HO2S High Signal - Bank 2 Sensor 2

44

D-GN

890

Fuel Tank Pressure Sensor Signal

45

PU/WH

1665

HO2S High Signal - Bank 1 Sensor 1

46

TN/WH

1653

HO2S Low Signal - Bank 1 Sensor 1

47

--

--

Not Used

48

WH

5279

HO2S Output Pump Current Bank 2 Sensor 1

49

L-GN

5278

HO2S Input Pump Current Bank 2 Sensor 1

50

--

--

Not Used

51

GY

2705

5-Volt Reference

52-56

--

--

Not Used