Conditions for Clearing the DTC

WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

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 non-emission related diagnostic.
Clear the DTC with a scan tool.

DTC P1550

Step	Action	Yes	No
1	Did you perform the Diagnostic System Check-Engine Controls?	Go to Step 2	Go to Diagnostic System Check - Engine Controls
2	Do any other DTCs set?	Go to Diagnostic Trouble Code (DTC) List	Go to Step 3
3	IMPORTANT: Use connection pin adapters from J 35616 Adapter Kit. Turn OFF the ignition. Disconnect the FICM connectors. Turn ON the ignition. Probe the FICM power circuits with a DMM connected to one of the FICM ground circuits. Does the voltage measure more than 10 volts?	Go to Step 5	Go to Step 4
4	Repair high resistance in the FICM power or ground circuits. Did you complete the repair?	Go to Step 6	-
5	Replace the FICM. Refer to Fuel Injection Control Module Replacement . Did you complete the replacement?	Go to Step 6	-
6	Use a scan tool to clear the DTCs. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC run and pass?	Go to Step 7	Go to Step 2
7	With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed?	Go to Diagnostic Trouble Code (DTC) List	System OK