Circuit Description
The PCM controls the fuel gage based on the fuel level signal. DTC P0656 will set when the PCM detects an improper voltage on the fuel gage signal circuit.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
| • | The PCM detects an improper voltage level at the fuel gage signal circuit. |
| • | The above condition is present for at least 30 seconds. |
Action Taken When the DTC Sets
The PCM will store conditions which were present when the DTC set as Failure Records data only. This information will not be stored as Freeze Frame data.
Conditions for Clearing the MIL/DTC
| • | A history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction. |
| • | The PCM receives the clear code command from the scan tool. |
Diagnostic Aids
| • | Use the Freeze Frame and/or Failure Records data in order to locate an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame and/or Failure Records data may aid in determining the number of miles since the DTC set. The Fail Counter and Pass Counter can also aid in determining the number of ignition cycles that the diagnostic reported a pass and/or fail. Operate the vehicle within the same freeze frame conditions (RPM, load, vehicle speed, temperature, etc.). This will isolate when the DTC failed. |
| • | Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: Instrument Cluster Schematics | ||||
1 | Did you perform the IPC Diagnostic System Check? | -- | Go to Step 2 | |
2 |
Is the voltage near the specified value? | B+ | Go to Step 3 | Go to Step 4 |
3 |
Is the voltage at the specified value? | 0.0 V | Go to Step 6 | Go to Step 7 |
4 | Test the fuel gage signal circuit for an open, for a high resistance, or for a short to ground. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 10 | Go to Step 5 |
5 | Inspect for poor connections at the harness connector of the IPC. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 10 | Go to Step 8 |
6 | Inspect for poor connections at the harness connector of the PCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 10 | Go to Step 9 |
7 | Repair the short to voltage in the fuel gage signal circuit. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 10 | -- |
8 | Replace the IPC. Refer to Instrument Cluster Replacement . Did you complete the replacement? | -- | Go to Step 10 | -- |
9 |
Important:: Program the replacement PCM. Replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls (3.1L) or Powertrain Control Module Replacement in Engine Controls (3.8L). Did you complete the replacement? | -- | Go to Step 10 | -- |
10 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
