Conditions for Clearing the DTC

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.

Step	Action	Yes	No
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Engine Control Module (ECM) Connector End Views
1	Did you perform the Diagnostic System Check - Engine Controls?	Go to Step 2	Go to Diagnostic System Check - Engine Controls
2	Start the engine. Allow the engine to idle for 1 minute. Does DTC P0656 fail this ignition?	Go to Step 4	Go to Step 3
3	Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records. Did the DTC fail this ignition?	Go to Step 4	Go to Intermittent Conditions
4	Are DTCs P0654 and P1668 also set?	Go to Step 7	Go to Step 5
5	Turn OFF the ignition. Disconnect the engine control module (ECM). Install one lead of the J 33431-C Signal Generator and Instrument Panel Tester to the fuel gage signal circuit at the ECM harness connector, and the other lead to a good ground. Turn ON the ignition, with the engine OFF. Set the J 33431-C to generate a speedometer signal. Does the fuel gage change?	Go to Step 9	Go to Step 6
6	Test the fuel gage signal circuit for the following conditions: An open A short to ground A short to voltage High resistance Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 13	Go to Step 10
7	Test the ignition 1 voltage circuit of the instrument panel cluster (IPC) for the following conditions: An open A short to ground An open fuse A short to voltage High resistance Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 13	Go to Step 8
8	Test the ground circuit of the instrument panel cluster (IPC) for an open circuit or for high resistance. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 13	Go to Step 10
9	Inspect for poor connections at harness connector of the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 13	Go to Step 11
10	Inspect for poor connections at the harness connector of the IPC. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 13	Go to Step 12
11	Replace the ECM. Refer to Engine Control Module (ECM) Replacement . Did you complete the replacement?	Go to Step 13	-
12	Replace the IPC. Refer to Instrument Panel Cluster (IPC) Replacement . Did you complete the replacement?	Go to Step 13	-
13	Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records. Did the DTC fail this ignition?	Go to Step 2	Go to Step 14
14	Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?	Diagnostic Trouble Code (DTC) List	System OK