Circuit Description
The PCM provides ignition positive voltage to energize the fuel pump relay. The fuel pump relay supplies power to the fuel pump. When the ignition switch is first turned ON, the PCM energizes the fuel pump relay for approximately 2 seconds. This allows the fuel pump to prime the fuel rail assembly. The fuel pump relay remains ON as long as the PCM receives reference pulses from the ICM (engine is cranking or running). If the PCM does not receive the reference pulses, the PCM de-energizes the fuel pump relay. The PCM monitors the fuel pump ignition positive feed circuit and has the ability to detect an electrical malfunction. If the PCM detects an electrical malfunction on the fuel pump ignition positive feed circuit, DTC P0230 will set.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
| • | The PCM detects an electrical malfunction on the fuel pump relay control circuit. |
| • | The condition is present for 0.5 second. |
Diagnostic Aids
An intermittent may be caused by a poor connection, rubbed through the wire insulation or a wire broken inside of the insulation.
Check for the following conditions:
| • | Poor connections at the PCM or fuel pump relay. |
| Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection. |
| • | Damaged harness |
| Inspect the wiring harness for damage. |
Reviewing the Fail Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.
Test Description
Number(s) below refer to the step number(s) on the Diagnostic Table:
-
Ensures that the fuel pump relay control circuit and the PCM are capable of controlling the fuel pump relay. Using the scan tool to command the fuel pump allows only a 2 second time in the commanded state.
-
Checks the fuel pump control circuit for a short to ground.
-
Checks the fuel pump control circuit for an open.
-
This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is being replaced, the new PCM must be programmed.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | ||
Does the test light turn ON when the fuel pump is commanded ON? | -- | |||
Is the test light ON? | -- | |||
4 | Probe the fuel pump relay ground circuit with a test light connected to B+. Is the test light ON? | -- | ||
Was a problem found? | -- | |||
6 |
Was a problem found? | -- | ||
7 |
Is the test light ON? | -- | ||
8 |
Was a problem found? | -- | ||
9 | Locate and repair short to ground in the fuel pump relay control circuit. Refer to Repair Procedures in Wiring Repairs . Is action complete? | -- | -- | |
10 | Locate and repair open the fuel pump relay ground circuit. Refer to Repair Procedures in Wiring Repairs . Is action complete? | -- | -- | |
11 | Replace the fuel pump relay. Refer to Fuel Pump Relay Replacement . Is action complete? | -- | -- | |
Replace the PCM Important: : The replacement PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming . Is action complete? | -- | -- | ||
13 | Locate and repair the short to voltage in the fuel pump control circuit. Is action complete? | -- | -- | |
14 |
Does the scan tool indicate DTC P0230 failed this ignition? | -- | System OK |
