ECD SYSTEM Fuel Pump Control Circuit
| DTC Code | DTC Name |
|---|---|
| Fuel Pump Control Circuit |
DESCRIPTION
When the engine is cranked, the ST (starter) relay drive signal is input to the STA terminal of the ECM, and the NE signal generated by the crankshaft position sensor is also input to the NE+ terminal. Thus, the ECM interprets that the engine has been cranked, current flows to the FUEL PUMP relay, and the fuel pump (fuel suction with pump and gauge tube assembly) operates.
While the NE signal is input to the ECM with the engine running, the fuel pump operates continuously.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
When replacing the ECM, the ECM needs registration and initialization.
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
When the ECM must be replaced, before replacing the ECM, perform the "Learning Values Save" function using the GTS. Then after installing the new ECM, perform all of the initialization/registrations for the "Learning Values Write" function by following the instructions shown on the GTS display.
Read freeze frame data using the GTS. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, and other data from the time the malfunction occurred.
PROCEDURE
PERFORM ACTIVE TEST USING GTS (ACTUATOR TEST OF FPC)
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Actuator Test of FPC.
Powertrain > Engine and ECT > Active Test
Tester Display
Actuator Test of FPC
Check whether the fuel pump operating sound occurs when performing the Active Test on the GTS.
Result
Result
Proceed to
Fuel pump operating sound does not occur
A
Fuel pump operating sound occurs
B
INSPECT NO. 1 INTEGRATION RELAY (FUEL PUMP RELAY)
Inspect the No. 1 integration relay.
Result
Proceed to
OK
NG
CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - ECM)
Remove the No. 1 integration relay from the engine room relay block and junction block.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection
Condition
Specified Condition
1J-2 - A50-60 (FC)
Always
Below 1 Ω
1J-2 or A50-60 (FC) - Body ground
Always
10 kΩ or higher
Result
Proceed to
OK
NG
NG REPAIR OR REPLACE HARNESS OR CONNECTOR
CHECK HARNESS AND CONNECTOR (FUEL PUMP RELAY - IG2 RELAY)
Remove the No. 1 integration relay from the engine room relay block and junction block.
Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection
Condition
Specified Condition
1J-3 - 1I-4
Always
Below 1 Ω
1J-3 or 1I-4 - Body ground
Always
10 kΩ or higher
Result
Proceed to
OK
NG
NG REPAIR OR REPLACE HARNESS OR CONNECTOR
CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - FUEL SUCTION WITH PUMP AND GAUGE TUBE ASSEMBLY - BODY GROUND)
Remove the No. 1 integration relay from the engine room relay block and junction block.
Disconnect the fuel pump (fuel suction with pump and gauge tube assembly) connector.
Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection
Condition
Specified Condition
1J-4 - L20-4 (B)
Always
Below 1 Ω
L20-5 (E) - Body ground
Always
Below 1 Ω
1J-4 or L20-4 (B) - Body ground
Always
10 kΩ or higher
Result
Proceed to
OK
NG
NG REPAIR OR REPLACE HARNESS OR CONNECTOR
INSPECT FUEL PUMP (FUEL SUCTION WITH PUMP AND GAUGE TUBE ASSEMBLY)
Inspect the fuel pump (fuel suction with pump and gauge tube assembly).
Result
Proceed to
OK
NG