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Trouble Code Definition

ECM/PCM TROUBLE CODE DEFINITION

Code No.

Circuit Affected

12 ⁽¹⁾

No RPM Reference Pulse

13

Single-Sensor Models

Oxygen Sensor Circuit Open

Dual-Sensor Models

Left Oxygen Sensor Circuit Open

14

Coolant Temperature Sensor Signal Voltage Low

15

Coolant Temperature Sensor Signal Voltage High

16

System Voltage Low (Except Lumina)

17

Camshaft Sensor (Except Lumina)

21

TPS Signal Voltage High

22

TPS Signal Voltage Low

23

MAT Sensor Signal Voltage High

24

Vehicle Speed Sensor

25

MAT Sensor Signal Voltage Low

28

Transmission Range Error (Except Lumina)

32

EGR System Error

33

MAP Sensor Signal Voltage High

34

MAP Sensor Signal Voltage Low

35

IAC Idle Speed Error

36

24X Signal Error (Except Lumina)

37

TCC Brake Switch (Except Lumina)

41

Ignition Control Circuit (Except Lumina)

43

ESC (Knock Sensor) Error

44

Single-Sensor Models

Lean Exhaust Indication

Dual-Sensor Models

Left Lean Exhaust Indication

45

Single-Sensor Models

Rich Exhaust Indication

Dual-Sensor Models

Left Rich Exhaust Indication

46

Pass-Key Circuit (Grand Prix)

51

Faulty PROM, MEM-CAL Or ECM/PCM

53

System Overvoltage

54

Fuel Pump Voltage Low

58

Transmission Fluid Temp. High

59

Transmission Fluid Temp. Low

61

Degraded O2 Sensor (Lumina)

62

Gear Switch Error (Lumina)

63

Right Oxygen Sensor Ckt Open (Dual-Sensor Models)

64

Right Oxygen Sensor Lean (Dual-Sensor Models)

66

A/C Pressure Sensor

67

A/C Pressure Sensor

70

High A/C Pressure (Except Lumina)

72

VSS Signal Error

75, 76, 77

EGR Sol. Error

80

Transmission Component Error

82

3X Signal Error

86

Analog/Digital Error

96

Trans. Voltage Low

⁽¹⁾	Display of a Code 12 is normal when reference pulses are not being received by control module (engine not running).

NOTE: Use trouble code charts only if SERVICE ENGINE SOON light is illuminated (indicating a current problem exists).