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Trouble Code Definition

ECM/PCM TROUBLE CODE DEFINITION

Code No. Circuit Affected
12 (1) No RPM Reference Pulse
13 Open Oxygen Sensor Circuit
14 CTS Signal Voltage Low
15 CTS Signal Voltage High
21 TPS Signal Voltage High
22 TPS Signal Voltage Low
23 MAT Sensor Signal Voltage High
24 Vehicle Speed Sensor Circuit
25 (IAT) MAT Sensor Signal Voltage Low
33 MAP Sensor Signal Voltage High
34 MAP Sensor Signal Voltage Low
41 Cylinder select Error
42 EST Circuit Open Or Grounded
43 ESC Error
44 Lean Exhaust Indication
45 Rich Exhaust Indication
46 Anti-Theft System Fault
51 Faulty PROM, MEM-CAL or ECM/PCM
52 Low Engine Oil Temperature
53 System Overvoltage
54 Fuel Pump Voltage Low
62 High Engine Oil Temperature
(1) Display of a Code 12 is normal when no reference pulses are received by control module (engine not running).
NOTE: Trouble code charts should only be used 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 first, then proceed to low profile numbered codes.