Circuit Description
The fuel level sensor changes resistance based on the fuel level. The PCM monitors the signal circuit of the fuel level sensor in order to determine the fuel level. When the fuel tank is full, the fuel level sensor resistance is high and the PCM senses a high fuel level sensor signal voltage. When the fuel tank is empty, the fuel level sensor resistance is low and the PCM senses a low fuel level sensor signal voltage. The PCM uses the signal circuit of the fuel level sensor in order to calculate the percentage of remaining fuel in the tank. The PCM sends the fuel level percentage via the fuel level signal circuit to the instrument panel cluster (IPC) in order to control the fuel gage.
The PCM monitors the voltage on the fuel level signal circuit. The PCM sets this DTC if the fuel level signal circuit to the IPC becomes open or shorted to ground.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
The PCM detects that the signal circuit is low for more than 5 seconds.
Action Taken When the DTC Sets
The PCM records the operating conditions at the time the diagnostic fails. The PCM stores the failure information in the Failure Records on the scan tool.
Conditions for Clearing the DTC
| • | The DTC becomes history when the conditions for setting the DTC are no longer present. |
| • | The history DTC clears after 40 malfunction free warm-up cycles. |
| • | 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 help in determining the number of miles since the DTC set. The Fail Counter and Pass Counter can also help determine the number of ignition cycles that the diagnostic reported a pass and/or fail. Operate the vehicle within the same freeze frame conditions including those for RPM, for engine load, for vehicle speed, for temperature, and for others. This will isolate when the DTC failed.
Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Instrument Cluster Schematics | |||
1 | Did you perform the Instrument Cluster Diagnostic System Check? | Go to Step 2 | |
2 | Is DTC P1665 a current code? | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems |
3 |
Important:: Verify the J 33431-C resistance settings with a DMM. Does the fuel gage move from empty to full? | Go to Step 6 | Go to Step 4 |
4 | Test the fuel level signal circuit for an open 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 9 | 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 to Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 9 | Go to Step 7 |
6 | Inspect for poor connections at the harness connector of the PCM. 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 9 | Go to Step 8 |
7 | Replace the IPC. Refer to Instrument Cluster Replacement . Did you complete the replacement? | Go to Step 9 | -- |
8 |
Important:: Program the replacement PCM. Replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls - 8.1L. Did you complete the replacement? | Go to Step 9 | -- |
9 |
Does the DTC reset? | Go to Step 2 | System OK |
