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2012
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G37 IPL, Automatic Trans
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Repair and Diagnosis (Single Page)
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Steering Control System (With 4WAS) (Coupe)
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DTC/Circuit Diagnosis
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DTC C1921: Engine Speed Signal
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DTC Logic
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DTC Detection Logic
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DTC Detection Logic
DTC
Items (CONSULT screen terms)
Diagnostic item is detected when...
Possible cause
C1921
ENG REV SIGNAL
Malfunction is detected in engine speed signal that is output from ECM via CAN communication. (Improper signal is input engine speed.)
Engine speed signal error