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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
Single O2 Sensor Oxygen Sensor Circuit Open
Dual O2 Sensors Left 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 MAT Sensor Signal Voltage High
24 Vehicle Speed Sensor
25 MAT Sensor Signal Voltage Low
26 Quad-Driver Error
28 Transmission Range Error
29 Quad-Driver Error
32 EGR System Error
33 MAP Sensor Signal Voltage High
34 MAP Sensor Signal Voltage Low
35 IAC Idle Speed Error
36 High Resolution Pulse
37 TCC Brake Switch
38 TCC Brake Switch
41 Opti-Spark Open Circuit
42 Opti-Spark Circuit Grounded
43 ESC (Knock Sensor) Error
44
Single O2 Sensor Lean Exhaust Indication
Dual O2 Sensors Left Lean Exhaust Indication
45
Single O2 Sensor Rich Exhaust Indication
Dual O2 Sensors Left Rich Exhaust Indication
46 Pass-Key Circuit
47 Knock Sensor Module
48 MAF Sensor
50 System Voltage Low
51 Faulty PROM, MEM-CAL Or ECM/PCM
53 System Overvoltage
55 ECM/PCM Error Fuel Lean Monitor
58 Transmission Fluid Temp. High
59 Transmission Fluid Temp. Low
61 A/C System Performance
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
68 A/C Relay Circuit
69 A/C Clutch Circuit
70 A/C Quad-Driver Module
71 Low A/C Temperature
72 VSS Signal Error
73 Pressure Control Solenoid
74 Traction Control Circuit
75 Transmission Voltage Low
77 Quad-Driver Module Primary Cooling Fan
78 Quad-Driver Module Secondary Cooling Fan
79 Transmission Voltage High
80 Transmission Component Error
81 Transmission 2-3 Error
82 Transmission 1-2 Error
84 Transmission 1-2 Error
85 TCC Stuck On
90 TCC Error
95 Change Oil Light
96 Low Oil Light
97 VSS Output
(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).