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Trouble Code Identification

ECM TROUBLE CODE IDENTIFICATION

Code

Circuit Affected

12

⁽¹⁾

21

TPS signal voltage high.

22

TPS signal voltage low.

24

VSS circuit.

31

MAP sensor signal voltage low.

32

EGR vacuum circuit.

33

MAP sensor signal voltage high.

51

PROM faulty or improperly installed.

52

Fault in ECM circuit.

53

5-volt reference circuit overloaded (grounded).

⁽¹⁾	Code 12 will be displayed only if no reference pulses are received by the ECM from the engine speed sensor. Code 12 is never a stored code.