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Trouble Code Definition

ECM/PCM TROUBLE CODE DEFINITION

Code No. Circuit Affected
11 MIL
12 (1) No RPM Reference Pulse
13 Left Heated Oxygen Sensor Circuit Open
14 Coolant Temperature Sensor Signal Voltage Low
15 Coolant Temperature Sensor Signal Voltage High
16 Low Resolution Pulse
18 Injector Circuits
21 TPS Signal Voltage High
22 TPS Signal Voltage Low
23 Intake Air Temperature Sensor Signal Voltage High
24 Vehicle Speed Sensor
25 Intake Air Temperature Sensor Signal Voltage Low
26 Quad-Driver Error
27 EGR Vacuum Control Signal Solenoid Valve Circuit
28 Transmission Range Pressure Switch Assembly Fault
29 Secondary Air Injection Pump Circuit
32 EGR System Error
33 MAP Sensor Signal Voltage High
34 MAP Sensor Signal Voltage Low
36 High Resolution Pulse
37 TCC Brake Switch Stuck ON
38 TCC Brake Switch Stuck OFF
41 Opti-Spark Open Circuit
42 Opti-Spark Circuit Shorted Or Grounded
43 ESC (Knock Sensor) Error
44 Left Heated Oxygen Sensor Lean Exhaust Indication
45 Left Heated Oxygen Sensor Rich Exhaust Indication
46 Pass-Key Circuit
47 Knock Sensor Circuit Or Module Missing
48 MAF Sensor
50 System Voltage Low
51 Faulty PROM, MEM-CAL Or ECM/PCM
53 System Overvoltage
55 Fuel Lean Monitor
58 Transmission Fluid Temp. High
59 Transmission Fluid Temp. Low
63 Right Heated Oxygen Sensor Circuit Open
64 Right Heated Oxygen Sensor Lean Exhaust Indication
65 Right Heated Oxygen Sensor Rich Exhaust Indication
66 A/C Pressure Sensor Open Or Shorted
67 A/C Pressure Sensor/Clutch Problem
68 A/C Relay Circuit Shorted
69 A/C Clutch Circuit
70 A/C Clutch Relay Driver Circuit
72 VSS Signal Loss
73 Pressure Control Solenoid Circuit (Current Error)
75 Transmission System Voltage Low
77 Primary Cooling Fan Relay Control Circuit
78 Secondary Cooling Fan Relay Control Circuit
79 Transmission Fluid Overtemp
80 Transmission Component Slipping
81 Transmission 2-3 Error
82 Transmission 1-2 Error
84 Transmission 3-2 Error
85 TCC Stuck On (A/T)
90 TCC Solenoid Circuit
95 Change Oil Light Circuit
96 Low Oil Light Circuit
97 VSS Output Circuit
(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).