[Fubeca]

From the linked thread above:

Conditions for Running the DTC

• The ignition is ON.

• DTCs P0112, P0113, P0116, P0117, P0118, P0128, P0502, P0503 are not set.

• The start-up IAT is more than -7°C (+20°F).

• The vehicle has a minimum ignition OFF time of 10 hours.

• DTC P0116 runs once per drive cycle when the above conditions are met.


Conditions for Setting the DTC

• The start-up ECT is more than the start-up IAT by 100°C (180°F). OR

• The start-up ECT is more than the start-up IAT by 15°C (27°F), then the vehicle must be driven for more than 400 seconds over 24 km/h (15 mph). If the IAT sensor temperature decreases more than 8°C (14°F), a block heater is detected and the test is aborted. If the IAT sensor temperature does not decrease, a block heater was not detected and DTC P0116 sets.


Action Taken When the DTC Sets

The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.

The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.


Conditions for Clearing the MIL/DTC

• The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.

• A current DTC, Last Test Failed, clears when the diagnostic runs and passes.

• A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.

• Clear the MIL and the DTC with a scan tool.

I don't know if this applies to all GMs or just the trucks.