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: 1673474  Size: CH

Connector Part Information

  • OEM: 15492335
  • Service: 88988373
  • Description: 56-Way F MX123 Series (BU)

Terminal Part Information

  • 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

1-6

--

--

Not Used

7

WH

17

Stop Lamp Switch Signal

8

--

--

Not Used

9

TN

2759

Low Reference

10-11

--

--

Not Used

12

BN/WH

419

MIL Control

13

D-GN/WH

465

Fuel Pump Relay Control

14-17

--

--

Not Used

18

D-BU

5985

Accessory Wake Up Serial Data

19

PK

439

Ignition 1 Voltage

20

RD/WH

540

Battery Positive Voltage

21-25

--

--

Not Used

26

YE

447

Starter Relay Coil Control

27-30

--

--

Not Used

31

YE/BK

6032

Low Reference

32

GY

6031

5-Volt Reference 2

33

WH/BK

1164

5-Volt Reference 2

34

GY

2709

5-Volt Reference 1

35

TN

1274

5-Volt Reference 1

36

BN

1271

Low Reference

37

PU

1272

Low Reference

38-39

--

--

Not Used

40

BN

5069

PWR/TRN Relay Control

41-43

--

--

Not Used

44

PU

30

Fuel Level Sensor Signal

45

--

--

Not Used

46

OG

6030

Brake Booster Vacuum Signal

47

D-BU

1161

APP Sensor 1 Signal

48

D-GN

890

Fuel Tank Pressure Sensor Signal

49

L-BU

1162

APP Sensor 2 Signal

50-52

--

--

Not Used

53

D-GN/WH

459

A/C Compressor Clutch Relay Control

54

D-BU

473

High Speed Cooling Fan Relay Control

55

WH

1310

EVAP Canister Vent Solenoid Control

56

--

--

Not Used

Engine Control Module (ECM) C2


Object Number: 1590596  Size: CH

Connector Part Information

  • OEM: 13574286
  • Service: 88988931
  • Description: 73-Way F 0.64 2.8 Series, Sealed (BK)

Terminal Part Information

  • Pins: 2-72
  • 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

PU

2121

IC 1 Control

2

TN

1664

HO2S Low Signal Sensor 1

3

PU/WH

1665

HO2S High Signal Sensor 1

4

PU/WH

1668

HO2S High Signal Sensor 2

5

TN/WH

1669

HO2S Low Signal Sensor 2

6

L-BU

1876

KS 2 Signal

7

GY

2303

KS 2 Signal

8

D-BU

496

KS 1 Signal

9

GY

1716

KS 1 Signal

10

--

--

Not Used

11

YE

581

TAC Motor Control - 1

12

BN

582

TAC Motor Control - 2

13

PK/BK

5290

Ignition 1 Voltage

14-15

--

--

Not Used

16

PK/BK

1746

Fuel Injector 3 Control

17

PU/WH

2128

IC 8 Control

18

D-GN/WH

2124

IC 4 Control

19

BN/WH

2130

Low Reference

20-22

--

--

Not Used

23

PK/BK

632

Low Reference

24

BK

2755

Low Reference

25-26

--

--

Not Used

27

YE/BK

1868

Low Reference

28

--

--

Not Used

29

TN

2752

Low Reference

30-31

--

--

Not Used

32

L-GN/BK

1745

Fuel Injector 2 Control

33

OG

2127

IC 7 Control

34

D-GN

2125

IC 5 Control

35

BN

2129

Low Reference

36-38

--

--

Not Used

39

OG

631

5-Volt Reference 1

40

GY

2705

5-Volt Reference 1

41

--

--

Not Used

42

TN

2760

Low Reference

43

L-GN

1867

5-Volt Reference 2

44

GY

2701

5-Volt Reference 2

45-47

--

--

Not Used

48

D-BU/WH

878

Fuel Injector 8 Control

49

TN/WH

845

Fuel Injector 5 Control

50-51

--

--

Not Used

52

YE/BK

846

Fuel Injector 6 Control

53

OG/WH

2122

IC 2 Control

54

L-BU/WH

2126

IC 6 Control

55

L-BU

2123

IC 3 Control

56-58

--

--

Not Used

59

BN/WH

633

CMP Sensor Signal

60

TN/WH

331

Oil Pressure Sensor Signal

61

--

--

Not Used

62

TN/BK

472

IAT Sensor Signal

63

D-BU/WH

1869

CKP Sensor Signal

64

D-GN

485

TP Sensor 1 Signal

65

--

--

Not Used

66

PU

486

TP Sensor 2 Signal

67

YE

492

MAF Sensor Signal

68

GY/WH

3113

HO2S Heater Low Control Sensor 1

69

BN

2391

HO2S Heater Low Control Sensor 2

70

L-BU/BK

844

Fuel Injector 4 Control

71

OG/BK

877

Fuel Injector 7 Control

72

TN

1744

Fuel Injector 1 Control

73

BK/WH

451

Ground

Engine Control Module (ECM) C3


Object Number: 1590596  Size: CH

Connector Part Information

  • OEM: 13584164
  • Service: 88988372
  • Description: 73-Way F 0.64 2.8 Series, Sealed (GY)

Terminal Part Information

  • 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

1-6

--

--

Not Used

7

OG

225

Generator Turn On Signal

8-9

--

--

Not Used

10

TN

5496

Cylinder 6 Shutoff Solenoid Control

11

D-BU

5491

Cylinder 1 Shutoff Solenoid Control

12-17

--

--

Not Used

18

BN

1174

Oil Level Switch Signal

19-20

--

--

Not Used

21

BK/WH

2751

Low Reference

22

--

--

Not Used

23

OG/BK

469

Low Reference

24-27

--

--

Not Used

28

L-BU/BK

6297

Low Reference

29

GY

23

Generator Field Duty Cycle Signal

30-32

--

--

Not Used

33

TN

2501

High Speed GMLAN Serial Data Bus -

34

--

--

Not Used

35

TN

2761

Low Reference

36

--

--

Not Used

37

GY

2700

5-Volt Reference 1

38

--

--

Not Used

39

GY

2704

5-Volt Reference 1

40-43

--

--

Not Used

44

L-BU

6295

5-Volt Reference 2

45

--

--

Not Used

46

OG/BK

1786

Park/Neutral Signal

47

--

--

Not Used

48

D-GN/WH

428

EVAP Canister Purge Solenoid Control

49

D-GN

335

Low Speed Cooling Fan Relay Control

50-52

--

--

Not Used

53

TN/BK

2500

High Speed GMLAN Serial Data Bus +

54

--

--

Not Used

55

YE

410

ECT Sensor Signal

56

--

--

Not Used

57

OG/BK

380

A/C Refrigerant Pressure Sensor Signal

58

--

--

Not Used

59

L-GN

432

MAP Sensor Signal

60-65

--

--

Not Used

66

OG

381

Vehicle Speed Signal

67

--

--

Not Used

68

WH

5497

Cylinder 7 Shutoff Solenoid Control

69

OG

5494

Cylinder 4 Shutoff Solenoid Control

70-73

--

--

Not Used