P0230

DTC P0230 FUEL PUMP PRIMARY CIRCUIT

CIRCUIT DESCRIPTION

DTC Detection Condition:

In the diagram, when the engine is cranked, current flows from terminal ST of the ignition switch to the starter relay coil and also current flows to terminal STA of the ECM (STA signal).

When the STA signal and NE signal are input to the ECM, the TN is turned ON, current flows to the coil of the circuit opening relay, the relay switches on, power is supplied to the fuel pump, and the fuel pump operates.

While the NE signal is generated (engine running), the ECM keeps the TN ON (circuit opening relay ON) and the fuel pump also keeps operating.
The fuel pump speed is controlled at two levels (high speed or low speed) by the condition of the engine (starting, light load, heavy load). When the engine starts (STA ON), the Tr2 in the ECM is OFF, so the fuel pump relay closes and battery positive voltage is applied directly to the fuel pump. The fuel pump operates at high speed.
After the engine starts during idling or light loads, since the Tr2 goes ON, power is supplied to the fuel pump via the fuel pump resistor. The fuel pump operates at low speed.
This DTC chart is based on the premise that the engine is started. If the engine is not started, proceed to the problem symptoms table.

Wiring Diagram:

Step 1:

Step 2 - 3:

INSPECTION PROCEDURE:

HINT: Read freeze frame data using the hand-held tester or the OBD II scan tool, as freeze frame data records the engine conditions when the malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the malfunction.