Conditions for Clearing the MIL/DTC

WARNING: This page is about a different car, the 2007 GMC Sierra and 2007 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The ECM will turn the MIL OFF after 3 consecutive trips that the diagnostic has been run and passed.
The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
The DTC can be cleared by using the scan tool Clear DTC Information function.

DTC P1258

Step	Action	Yes	No
Connector End View Reference: Cooling System Connector End Views
1	Did you perform the Diagnostic System Check - Vehicle?	Go to Step 2	Go to Diagnostic System Check - Vehicle
2	Check the engine cooling fans for proper operation. Are the engine cooling fans operative?	Go to Engine Overheating	Go to Symptoms - Engine Cooling