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: 328564  Size: CH

Connector Part Information

    • 12186584
    • 70-Way F (BK)

Pin

Wire Color

Circuit No.

Function

1

--

--

Not Used

2

GY

2365

Low Reference

3

BK

470

Low Reference

4

WH/BK

1164

5-Volt Reference

5

BK/WH

451

Ground

6

GY/BK

1467

Air Shift Switch Signal

7

L- BU

494

Engine Shut Off-Signal

8

TN/BK

1921

SAE J1708 Serial Data A

9

WH/BK

1922

SAE J1708 Serial Data B

10

TN

1997

Headlamp Washer Pump Control

11

BK/WH

1120

Engine Fan Clutch Control

12

PU

2656

Exhaust Brake Control

13-14

--

--

Not Used

15

PU

1589

Fuel Level Sensor Signal - Primary

16

L-GN

2081

Exhaust Brake Switch Relay

17

--

--

Not Used

18

PU

719

Low Reference & LG5

19

D-GN/WH

2665

PTO Enable

20

--

--

Not Used

21

RD

2013

High Idle Indicator Control

22

BN/WH

379

CPP Switch Signal

23-25

--

--

Not Used

26

D-BU

1936

Fuel Level Sensor Signal - Secondary

27

--

--

Not Used

28

BN/WH

419

MIL Control

29

--

--

Not Used

30

YE

32

Instrument Panel Lamp Fuse Supply Voltage

31

YE

447

Starter Relay Coil Control

32

L-BU

2221

Signal High - Rear

33

D-GN

2222

Signal Low - Rear

34

D-GN

2362

SAE J1939 Serial Data Bus-

35

D-BU

84

Cruise Control Set/Coast Switch Signal

36

D-GN /WH

817

Vehicle Speed Signal

37

--

--

Not Used

38

WH

121

Engine Speed Signal

39

--

--

Not Used

40

D-GN

534

High Idle Switch Signal

41-43

--

--

Not Used

44

GN/BK

87

Cruise Control Resume/Accel Switch Signal

45

BN

86

Cruise Control Release Signal

46-48

--

--

Not Used

49

L-GN

1478

Coolant Level Switch Signal

50

YE

2361

SAE J1939 Serial Data Bus+

51

--

--

Not Used

52

OG

1540

Battery Positive Voltage

53

OG

1540

Battery Positive Voltage

54-55

--

--

Not Used

56

L-GN

488

PTO On Switch-Signal

57

--

--

Not Used

58

PU

2663

PTO Set

59

GY

397

Cruise Control On Switch Signal

60

TN

2664

Coolant Fan Control

61

--

--

Not Used

62

D-GN/WH

459

A/C Compressor Clutch Relay Control

63

--

--

Not Used

64

L-BU

1320

CHMSL Supply Voltage/Stop Lamp Supply Voltage

65

BK/WH

251

Ground

66

D-BU

1161

APP Sensor 1 Signal

67

BK/WH

251

Ground

68-69

--

--

Not Used

70

PK

439

Ignition 1 Voltage

Engine Control Module (ECM) C2


Object Number: 328564  Size: CH

Connector Part Information

    • 12186584
    • 70-Way F (BK)

Pin

Wire Color

Circuit No.

Function

1

--

--

Not Used

2

WH

828

5-Volt Reference

3

GN

829

Low Reference

4-7

--

--

Not Used

8

BU

850

Intake Air Heater Indicator/Relay Control

9-17

--

--

Not Used

18

PK

833

Low Reference

19-21

--

--

Not Used

22

--

--

CKP Sensor - High

23

--

--

CKP Sensor - Low

24

GY

994

Oil Pressure Sensor Signal

25-26

--

--

Not Used

27

BN

849

Fuel Rail Pressure Sensor Signal

28-31

--

--

Not Used

32

BU

995

ECT Sensor Signal

33

GY

458

Oil Level Switch Signal

34

--

--

Not Used

35

BU

967

IAT Sensor Signal

36

GY

701

Fuel Injector 1 Control

37

PU

702

Fuel Injector 2 Control

38

BN

703

Fuel Injector 3 Control

39

GN

704

Fuel Injector 4 Control

40

PK

746

MAP Sensor Signal

41

BN

826

5-Volt Reference

42

BU

827

Low Reference

43

--

--

Not Used

44

WH

983

Low Reference

45

OG

984

Low Reference

46

YE

985

Low Reference

47

--

--

Not Used

48

BK

963

Top Camshaft Position Signal - High

49

WH

964

Top Camshaft Position Signal - Low

50-53

--

--

Not Used

54

BU

705

Fuel Injector 5 Control

55

GY

706

Fuel Injector 6 Control

56-57

--

--

Not Used

58

BU

965

Bottom Camshaft Position Signal - High

59

YE

966

Bottom Camshaft Position Signal - Low

60

--

--

Not Used

61

PK

854

Fuel Pressure Regulator Solenoid Control - PWM

62

PU

855

Low Reference

63-70

--

--

Not Used