123

UnclassifiedGeneral

What This Code Means

MIL flashing at 2 Hz (twice per second); Power Derate level 1 enforced; Maximum throttle position limited to 50%; Adaptive learning disabled; Closed loop allowed to stay at limit

Possible Causes

  • •Engine Coolant Temperature reading or estimate greater than 240 deg. F with engine rpm greater than 650
  • •Engine over temperature

Related General Motors Powertrain Fault Codes

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