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: 13510514
  • Service: 88988736
  • Description: 56-Way F Receptacle MX123 Series (BU)

Terminal Part Information

  • Pins: 7, 9, 12-13, 18, 20, 26, 33-37, 40, 44, 47-49, 53-55
  • Terminal/Tray: 33467-0003/23
  • Core/Insulation Crimp: H/H
  • Release Tool/Test Probe: J-38125-213/J-35616-64B (L-BU)
  • Pins: 10, 11, 47, 49, 69, 37, 38, 41
  • Terminal/Tray: 33467-0005/23
  • Core/Insulation Crimp: Pins 10, 11, 47, 49, 69 - K/K
  • Core/Insulation Crimp: Pins 37, 38, 41 - J/J
  • Core/Insulation Crimp: Pins 17, 18, 19, 20, 26, 27, 29, 30, 37, 40 - J/J
  • Core/Insulation Crimp: Pins 6, 7, 8, 9, 19, 20, 21, 22, 23, 32, 35, 36, 37, 38, 39, 42, 48, 49, 52, 56, 57, 58, 59, 62, 67, 71, 72 - J/J
  • Release Tool/Test Probe: J-38125-213/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 or Stop Lamp Supply Voltage

8

--

--

Not Used

9

OG/BK

1057

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

BN

4

Accessory Voltage

19

PK

639

Ignition 1 Voltage

20

RD/WH

540

Battery Positive Voltage

21-25

--

--

Not Used

26

PU/WH

6386

Starter Relay Control

27-32

--

--

Not Used

33

WH/BK

1164

5-Volt Reference

34

GY

705

5-Volt Reference

35

TN

1274

5-Volt Reference

36

BN

1271

Low Reference

37

PU

1272

Low Reference

38

--

--

Not Used

39

BN

818

Vehicle Speed Signal

40

BN

5069

Main Relay Control

41-43

--

--

Not Used

44

PU

1589

Fuel Level Sensor Signal

45-46

--

--

Not Used

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: 1650395  Size: CH

Connector Part Information

  • OEM: 13547243
  • Service: See Catalog
  • Description: 73-Way F Receptacle 0.64 2.8 Series Sealed (BK)

Terminal Part Information

  • Pins: 1, 14, 15, 17, 24, 27, 29, 30, 31, 33, 34, 43, 44, 46, 47, 50, 51, 53, 54, 63, 64, 66, 68, 69
  • Terminal/Tray: 33467-0003/23
  • Core/Insulation Crimp: H/H
  • Release Tool/Test Probe: J-38125-213/J-35616-64B (L-BU)
  • Pins: 1, 14, 17, 20, 23, 24, 27, 29, 30, 33, 35, 36, 39, 42, 43, 44, 46, 50, 53, 56, 59, 62, 63, 64, 66, 67, 2, 3, 8, 12, 13, 16, 21, 22, 24, 32, 33, 34, 35, 41, 43, 44, 50, 52, 53, 58, 61, 63, 64, 65, 66, 68, 69, 70, 71, 72, 78
  • Terminal/Tray: 33467-0003/23
  • Core/Insulation Crimp: Pins 1, 14, 17, 20, 23, 24, 27, 29, 30, 33, 35, 36, 39, 42, 43, 44, 46, 50, 53, 56, 59, 62, 63, 64, 66, 67 - H/H
  • Core/Insulation Crimp: Pins 2, 3, 8, 12, 13, 16, 21, 22, 24, 32, 33, 34, 35, 41, 43, 44, 50, 52, 53, 58, 61, 63, 64, 65, 66, 68, 69, 70, 71, 72, 78 - H/H
  • Core/Insulation Crimp: Pins 17, 18, 19, 20, 26, 27, 29, 30, 37, 40 - J/J
  • Core/Insulation Crimp: Pins 6, 7, 8, 9, 19, 20, 21, 22, 23, 32, 35, 36, 37, 38, 39, 42, 48, 49, 52, 56, 57, 58, 59, 62, 67, 71, 72 - J/J
  • Release Tool/Test Probe: J-38125-213/J-35616-64B (L-BU)
  • Pins: 2, 3, 4, 5, 8, 9, 32, 48, 68, 69, 71, 72, 11, 12, 13, 17, 18, 19, 20, 26, 27, 29, 30, 37, 40, 6, 7, 8, 9, 19, 20, 21, 22, 23, 32, 35, 36, 37, 38, 39, 42, 48, 49, 52, 56, 57, 58, 59, 62, 67, 71, 72
  • Terminal/Tray: 33467-0005/23
  • Core/Insulation Crimp: Pins 2, 3, 4, 5, 8, 9, 32, 48, 68, 69, 71, 72 - J/J
  • Core/Insulation Crimp: Pins 11, 12, 13 - K/K
  • Core/Insulation Crimp: Pins 17, 18, 19, 20, 26, 27, 29, 30, 37, 40 - J/J
  • Core/Insulation Crimp: Pins 6, 7, 8, 9, 19, 20, 21, 22, 23, 32, 35, 36, 37, 38, 39, 42, 48, 49, 52, 56, 57, 58, 59, 62, 67, 71, 72 - J/J
  • Release Tool/Test Probe: J-38125-213/J-35616-64B (L-BU)

Engine Control Module (ECM) C2

Pin

Wire Color

Circuit No.

Function

1

PU

2121

IC 1 Control

2

TN/WH

3111

HO2S Low Signal Bank 1 Sensor 1

3

PU/WH

3110

HO2S High Signal Bank 1 Sensor 1

4

PU

3120

HO2S High Signal Bank 1 Sensor 2

5

TN/WH

3121

HO2S Low Signal Bank 1 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

PU

5284

CMP Actuator Solenoid Signal Bank 1 Intake

15

OG/BK

5272

CMP Actuator Solenoid Signal Bank 2 Intake

16

--

--

Not Used

17

OG/WH

2122

IC 2 Control

18

--

--

Not Used

19

PK

6414

ECM Low Reference

20

GY

5296

CMP Sensor Low Reference Bank 1 Exhaust

21

BN/WH

5303

CMP Sensor Low Reference Bank 2 Intake

22

BN

5299

CMP Sensor Low Reference Bank 2 Exhaust

23

TN

5301

CMP Sensor Low Reference Bank 1 Intake

24

BK

2755

Low Reference

25-26

--

--

Not Used

27

PU

574

Low Reference

28

--

--

Not Used

29

TN

2752

Low Reference

30

BN/WH

6754

CMP Actuator Solenoid Bank 1 Exhaust

31

D-BU

6755

CMP Actuator Solenoid Bank 2 Exhaust

32

L-BU/BK

844

Fuel Injector 4 Control

33

L-BU

2123

IC 3 Control

34

L-BU/WH

2126

IC 6 Control

35

PU

6413

Low Reference

36

YE/BK

5297

CMP Sensor 5-Volt Reference Bank 1 Exhaust

37

L-BU

5302

CMP Sensor 5-Volt Reference Bank 2 Intake

38

L-GN

5298

CMP Sensor 5-Volt Reference Bank 2 Exhaust

39

D-BU

5300

CMP Sensor 5-Volt Reference Bank 1 Intake

40-41

--

--

Not Used

42

TN/BK

2760

Low Reference

43

L-GN

2867

5-Volt Reference 2

44

GY

2701

5-Volt Reference 2

45

--

--

Not Used

46

BN

6753

CMP Actuator Solenoid Bank 1 Intake

47

D-BU/WH

6756

CMP Actuator Solenoid Bank 2 Intake

48

L-GN/BK

1745

Fuel Injector 2 Control

49

YE/BK

846

Fuel Injector 6 Control

50

L-GN

5282

CMP Actuator Solenoid Signal Bank 1 Exhaust

51

WH/BK

5283

CMP Actuator Solenoid Signal Bank 2 Exhaust

52

TN/WH

845

Fuel Injector 5 Control

53

D-GN/WH

2124

IC 4 Control

54

D-GN

2125

IC 5 Control

55

--

--

Not Used

56

D-GN

5273

CMP Signal Bank 1 Exhaust

57

YE

5276

CMP Signal Bank 2 Intake

58

PU

5274

CMP Signal Bank 2 Exhaust

59

OG

5275

CMP Signal Bank 1 Intake

60-61

--

--

Not Used

62

TN

472

IAT Sensor Signal

63

YE

573

CKP Sensor [1] 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 Bank 1 Sensor 1

69

GY/WH

3122

HO2S Heater Low Control Bank 1 Sensor 2

70

--

--

Not Used

71

PK/BK

1746

Fuel Injector 3 Control

72

TN

1744

Fuel Injector 1 Control

73

BK/WH

451

Ground

Engine Control Module (ECM) C3


Object Number: 1650395  Size: CH

Connector Part Information

  • OEM: 13542577
  • Service: See Catalog
  • Description: 73-Way F Receptacle 0.64 (BK)

Terminal Part Information

  • Pins: 7, 15, 21, 24, 29, 32, 33, 37, 46, 49, 50, 53, 57, 64, 65
  • Terminal/Tray: 33467-0003/23
  • Core/Insulation Crimp: H/H
  • Release Tool/Test Probe: J-38125-213/J-35616-64B (L-BU)
  • Pins: 3, 4, 5, 6, 23, 35, 39, 48, 55, 59
  • Terminal/Tray: 33467-0005/23
  • Core/Insulation Crimp: Pins 3, 4, 5, 6 - K/K
  • Core/Insulation Crimp: Pins 23, 35, 39, 48, 55, 59 - J/J
  • Core/Insulation Crimp: Pins 17, 18, 19, 20, 26, 27, 29, 30, 37, 40 - J/J
  • Core/Insulation Crimp: Pins 6, 7, 8, 9, 19, 20, 21, 22, 23, 32, 35, 36, 37, 38, 39, 42, 48, 49, 52, 56, 57, 58, 59, 62, 67, 71, 72 - J/J
  • Release Tool/Test Probe: J-38125-213/J-35616-64B (L-BU)

Engine Control Module (ECM) C3

Pin

Wire Color

Circuit No.

Function

1-2

--

--

Not Used

3

TN/WH

3211

HO2S Low Signal Bank 2 Sensor 1

4

PU/WH

3210

HO2S High Signal Bank 2 Sensor 1

5

PU

3220

HO2S High Signal Bank 2 Sensor 2

6

TN

3221

HO2S Low Signal Bank 2 Sensor 2

7

OG

225

Generator Turn On Signal

8-14

--

--

Not Used

15

L-GN

3212

HO2S Heater Low Control Bank 2 Sensor 1

16-20

--

--

Not Used

21

TN

5514

Low Reference

22

--

--

Not Used

23

OG/BK

469

Low Reference

24

TN/WH

2759

Low Reference

25-28

--

--

Not Used

29

GY

23

Generator Field Duty Cycle Signal

30-31

--

--

Not Used

32

OG

6392

IMT Valve Control

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

38

--

--

Not Used

39

GY

2704

5-Volt Reference

40-45

--

--

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

OG/WH

3223

HO2S Heater Low Control Bank 2 Sensor 2

51-52

--

--

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

60-63

--

--

Not Used

64

YE/BK

6806

IMT Valve SIgnal

65

TN/BK

231

Oil Pressure Switch Signal

66-73

--

--

Not Used