| Table 1: | Fuel Pump Relay |
Circuit Description
The PCM provides ignition positive voltage to control the fuel pump relay. The PCM has the ability to detect an electrical malfunction on the relay control circuit. When the ignition switch is first turned ON, the PCM energizes the fuel pump relay which applies power to the fuel pump. The fuel pump relay will remain ON as long as the engine is running or cranking and the PCM is receiving reference pulses. If no reference pulses are present, the PCM de-energizes the fuel pump relay within 2 seconds after the ignition is turned ON or the engine is stopped. With the engine stopped, the fuel pump can be turned ON by using the scan tool output controls function. If an electrical malfunction is detected, the PCM will set DTC P0230.
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. |
Action Taken When the DTC Sets
| • | The powertrain control module (PCM) stores the DTC information into memory when the diagnostic runs and fails. |
| • | The malfunction indicator lamp (MIL) will not illuminate. |
| • | The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Failure Records. |
Conditions for Clearing the MIL/DTC
| • | A History DTC will clear after forty consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic. |
| • | A last test failed (Current DTC) will clear when the diagnostic runs and does not fail. |
| • | Use a scan tool in order to clear the MIL/DTC. |
| • | Interrupting the PCM battery voltage may or may not clear DTCs. This practice is not recommended. Refer to Powertrain Control Module Description , Clearing Diagnostic Trouble Codes. |
Diagnostic Aids
Notice: Use the connector test adapter kit J 35616-A for any test that
requires probing the following items:
• The PCM harness connectors • The electrical center fuse/relay cavities • The component terminals • The component harness connector
Reviewing the Failure 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.
If the problem is intermittent, refer to Intermittent Conditions .
Relay Terminal Identification
Use the following relay cavity table in order to locate the correct cavities to probe during diagnosis. The table layout corresponds to the cavity layout in the Underhood Accessory Wiring Junction Block. Four blade relays can be inserted two ways. Use the table and NOT the numbering on the relay to avoid probing incorrectly.
Top of Junction Block | |
|---|---|
Switch Power (Fuse) | Coil Power (PCM) |
Not Used | -- |
Coil Ground | Switch Load (Pump) |
Test Description
Number(s) below refer to the step number(s) on the Diagnostic Table:
-
If the fuel pump is not audible at the fuel tank area, listen underhood at the fuel rail. Fuel flowing through the pressure regulator produces an audible hiss.
-
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 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | ||
Turn the key to Off, wait 15 seconds, then turn the key to On and listen for fuel pump operation. The fuel pump should operate for 2 seconds after the key is turned to On. The fuel pump can also be commanded on using the scan tool if necessary. Does the fuel pump turn on and off? | -- | Refer to Diagnostic Aids. | ||
3 | Is the fuel pump always on? | -- | ||
4 |
Does the test light turn On when the fuel pump is commanded On? | -- | ||
5 | Probe the fuel pump relay ground circuit with test light J 35616-200 connected to B+. Is the test light On? | -- | ||
6 |
Is the test light On? | -- | ||
7 |
Was a problem found and corrected? | -- | ||
8 |
Was a problem found and corrected? | -- | ||
9 |
Is the fuel pump running? | -- | ||
10 |
Was a problem found and corrected? | -- | ||
11 | Locate and repair short to ground in the fuel pump relay control circuit. Is the action complete? | -- | -- | |
12 | Locate and repair open the fuel pump relay ground circuit. Is the action complete? | -- | -- | |
13 | Locate and repair the short to voltage in the fuel pump relay control circuit. Is the action complete? | -- | -- | |
14 | Replace the fuel pump relay. Refer to Fuel Pump Relay Replacement . Is the action complete? | -- | -- | |
Replace the PCM Important: : The replacement PCM must be programmed. Refer to Powertrain Control Module Replacement/Programming . Is action complete? | -- | -- | ||
16 |
Does the scan tool indicate that this test ran and passed? | -- | ||
17 | Review Captured Info using the scan tool. Are there any DTCs that have not been diagnosed? | -- | Go to the applicable DTC table | System OK |
