P0230

1UR-FSE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0230: Fuel Pump Primary Circuit

DTC P0230 - Fuel Pump Primary Circuit

DESCRIPTION

When the engine is cranked, a signal is sent from the power source control ECU's STSW terminal to the ECM's STSW terminal. Then voltage travels from the ECM's STAR terminal through the park/neutral position switch to the ST relay coil. The STAR terminal also sends a signal to the STA terminal. When the STA signal and NE signal are input to the ECM, Tr1 inside the ECM turns ON, which causes power to be supplied to the C/OPN relay coil (C/OPN ON). As a result, the F/PMP relay actuates, which causes the fuel pump to operate. If the engine is operating and NE signals are being output, Tr1 inside the ECM is ON (C/OPN ON), and the fuel pump will continue operating. The fuel pump has high and low speed settings. When the engine is starting or operating with a heavy load, Tr2 inside the ECM turns ON to actuate the F/PMP relay so that the fuel pump operates at the high speed setting. When the engine is idling or operating with a light load, Tr2 turns OFF, and current flows through the fuel pump resistor to the fuel pump so that the fuel pump operates at the low speed setting.









WIRING DIAGRAM





This troubleshooting procedure is based on the premise that the engine is started. If the engine is not started, proceed to the problem symptoms table Symptom Related Diagnostic Procedures.

INSPECTION PROCEDURE
HINT: Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

PROCEDURE

1. CHECK FUEL PUMP (FUEL PUMP OPERATION)
(a) Check the fuel pump operation Testing and Inspection.
NG -- GO TO FUEL PUMP CONTROL CIRCUIT
OK -- Continue to next step.

2. CHECK ECM (FRP VOLTAGE)




(a) Measure the voltage according to the value(s) in the table below.
Standard voltage:






NG -- INSPECT FUEL PUMP RELAY (F/PMP)
OK -- REPLACE ECM
3. INSPECT FUEL PUMP RELAY (F/PMP)




(a) Remove the F/PMP relay from the engine room No. 2 relay block.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:





(c) Reinstall the F/PMP relay.
NG -- REPLACE FUEL PUMP RELAY (F/PMP)
OK -- Continue to next step.

4. CHECK HARNESS AND CONNECTOR (F/PMP RELAY - ECM)




(a) Remove the F/PMP relay from the engine room No. 2 relay block.
(b) Disconnect the ECM connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance (Check for open):






Standard resistance (Check for short):





(d) Reinstall the F/PMP relay.
(e) Reconnect the ECM connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR (F-PMP RELAY - C/OPN RELAY)