GM
Type:
    Powertrain - Manufacturer Controlled DTC - Manufacturer Controlled
Description:
    ICM 24X Reference Circuit Low Frequency
Cause:
    DTC P0340 and P1376 not set, at least 7 CAM edges received this ignition cycle, at least one CAM REF pulse received within the last 4 seconds, engine speed over 496 rpm, then the PCM did not detect any 24X REF pulses (24X circuit was low for 4 seconds)