Circuit Description
The PCM controls the fuel pump relay by supplying switched ignition voltage to the fuel pump relay coil. When the ignition switch is first turned On, the PCM energizes the fuel pump relay. The relay contacts close applying 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. With the engine stopped, the fuel pump can be turned On with a scan tool.
If the PCM detects a problem on the relay control circuit, DTC P0230 will set. Use this table if DTC P0230 is not set and a problem exists with the fuel pump.
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
If the problem is intermittent, refer to Intermittent Conditions .
Test Description
Number(s) below refer to the step number(s) on the Diagnostic Table:
-
Verifies whether or not a fault is present at this time.
-
The P0230 diagnostic handles the control portion of the relay circuit. If DTC P0230 is set, perform that diagnostic first.
-
Check for poor connections/terminal tension at the fuse. Refer to Intermittents and Poor Connections Diagnosis .
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | ||
Turn the fuel pump on using the scan tool. Is the fuel pump running? | -- | Refer to Diagnostic Aids . | ||
Is DTC P0230 set? | -- | |||
Check the fuel pump system fuse. Is the fuse OK? | -- | |||
5 |
Is the resistance more than the specified value? | 2 Ohms | ||
6 |
Is the resistance more than the specified value? | 2 Ohms | ||
7 |
Is the fuse OK? | -- | ||
8 |
Is the fuse OK? | -- | Refer to Diagnostic Aids. | |
9 |
Is the test lamp on? | -- | ||
10 | Connect the B+ feed circuit to the fuel pump feed circuit in the relay connector using a 15 Amp fused jumper. Is the fuel pump running? | -- | ||
11 |
Is the test light on? | -- | ||
12 |
Is the test light on? | -- | ||
13 | Repair the short to ground in the B+ feed circuit to the relay. Is the action complete? | -- | -- | |
14 | Repair the short to ground in the fuel pump feed circuit. Is the action complete? | -- | -- | |
15 | Repair the open/high resistance B+ feed circuit to the relay. Is the action complete? | -- | -- | |
16 | Repair the open/high resistance fuel pump feed circuit. Is the action complete? | -- | -- | |
17 | Repair the open/high resistance fuel pump ground circuit. Is the action complete? | -- | -- | |
18 | Check for poor connections/terminal tension at the relay connector. Refer to Intermittents and Poor Connections Diagnosis . Was a problem found and corrected? | -- | ||
19 | Replace the relay. Is the action complete? | -- | -- | |
20 | Check for poor connections/terminal tension at the fuel pump connector. Refer to Intermittents and Poor Connections Diagnosis . Was a problem found and corrected? | -- | ||
21 | Replace the fuel pump. Is the action complete? | -- | -- | |
22 | Turn the fuel pump on using the scan tool. Is the fuel pump running? | -- | System OK |
