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Trouble Code Definition

ECM/PCM TROUBLE CODE DEFINITION

Code No. Circuit Affected
12 (1) No RPM Reference Pulse
13 Oxygen Sensor Circuit Open Left Oxygen Sensor Circuit Open (Dual-Sensor Models)
14 Coolant Temperature Sensor Signal Voltage Low
15 Coolant Temperature Sensor Signal Voltage High
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
32 EGR System Error
33 MAP Sensor Signal Voltage High
34 MAP Sensor Signal Voltage Low
35 IAC Idle Speed Error
42 EST Circuit Open Or Grounded
43 ESC Error
44 Lean Exhaust Indication Left Lean Exhaust Indication (Dual-Sensor Models)
45 Rich Exhaust Indication Left Rich Exhaust Indication (Dual-Sensor Models)
51 Faulty PROM, MEM-CAL Or ECM/PCM
52 Faulty/Missing CAL-PAC Or MEM-CAL
53 System Overvoltage
54 Fuel Pump Voltage Low
55 ECM/PCM Error
61 A/C System Performance
63 Right Oxygen Sensor Circuit Open (Dual-Sensor Models)
64 Right Oxygen Sensor Lean (Dual-Sensor Models)
65 Right Oxygen Sensor Rich (Dual-Sensor Models)
66 A/C Pressure Sensor
85 PROM Error
87 EEPROM Error
(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). Exceptions are Code 13, 15, 24, 44 and 45 charts, which may be used to help diagnose intermittent codes. Anytime control module-related Codes 51, 52 or 55 are displayed with another code, start with 50-series code, and then proceed to lower numbered codes.