Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptor
DTC P0230: Fuel Pump Relay Control CircuitDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Battery Voltage - Relay Switch Side | ¹ | ² | -- | -- |
Fuel Pump Supply Voltage | ¹ | ² | ³ | -- |
Fuel Pump Relay Control | P0230 | P0230 | P0230 | -- |
Fuel Pump Relay Ground | -- | P0230 | -- | -- |
Fuel Pump Ground | -- | ² | -- | -- |
¹Blown fuel pump fuse, cranks no start ²Cranks no start ³Fuel pump operates continuously, then discharged battery | ||||
Circuit/System Description
The engine control module (ECM) enables the fuel pump relay when the ignition switch is turned ON. The ECM will disable the fuel pump relay within 2 seconds unless the ECM detects ignition reference pulses. The ECM continues to enable the fuel pump relay as long as ignition reference pulses are detected. The ECM disables the fuel pump relay within 2 seconds if ignition reference pulses cease to be detected and the ignition remains ON.
The ECM monitors the voltage on the fuel pump relay control circuit. If the ECM detects an incorrect voltage on the fuel pump relay control circuit, a fuel pump relay control DTC sets.
Conditions for Running the DTC
| • | The ignition is ON. |
| • | The system voltage is between 9-18 volts. |
| • | DTC P0230 runs continuously when the above conditions are met. |
Conditions for Setting the DTC
| • | The ECM detects that the commanded state of the driver and the actual state of the control circuit do not match. |
| • | The above condition is met for a minimum of 2.5 seconds. |
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | 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 emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
Reference Information
Schematic Reference
Connector End View Reference
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
Note: An open or a short to voltage in the control circuit will cause both the Ckt. Open Test Status and the Ckt. Short Volts Test Status parameters to display Fault.
Ignition ON, command the fuel pump relay ON and OFF with a scan tool while observing the following control circuit status parameters:
| • | Fuel Pump Relay Ckt. Short Gnd Test Status |
| • | Fuel Pump Relay Ckt. Open Test Status |
| • | Fuel Pump Relay Ckt. Short Volts Test Status |
Each parameter should toggle between OK and Not Run or Not Run and OK.
Circuit/System Testing
- With the ignition OFF, remove the fuel pump relay from the rear electrical center.
- With the ignition ON, engine OFF, probe the control circuit of the fuel pump relay with a test lamp that is connected to a good ground. Command the fuel pump relay ON and OFF with a scan tool. The test lamp should turn ON and OFF with each command.
- Connect a test lamp between the control circuit of the fuel pump relay and the ground circuit of the fuel pump relay. Command the fuel pump relay ON and OFF with a scan tool.
| ⇒ | If the test lamp does not turn ON and OFF, test for an open or a short to ground in the fuel pump relay control circuit, an intermittent or a poor connection at the ECM. If the circuit tests normal, replace the ECM. |
| ⇒ | If the test lamp remains illuminated with each command, test for a short to voltage in the control circuit of the fuel pump relay or an intermittent or a poor connection at the ECM. If the circuit tests normal, replace the ECM. |
| ⇒ | If the test lamp does not turn ON and OFF, repair the open or the high resistance in the ground circuit of the fuel pump relay. |
| ⇒ | If the test lamp does turn ON and OFF, test for an intermittent and for a poor connection at the fuel pump relay, or a faulty fuel pump relay. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for ECM replacement, setup, and programming
