DTC P0230: Fuel Pump Primary Circuit [02/2014 - 11/2016]: Description

WARNING: This page is about a different car, the 2016 Toyota Highlander, 2015 Toyota Highlander, and 2014 Toyota Highlander. However, it is still accessible from the selected car via links, so may be relevant.

The FUEL PMP relay switches the fuel pump speed according to the engine conditions. The fuel pump operates when the ECM receives the NE signal. The FUEL PMP relay is turned on while the engine is idling or operating at low load. This causes current to flow through the fuel pump resistor to the fuel pump. The fuel pump then operates at low speed. The FUEL PMP relay is turned off while the engine is cranking or operating at high load. The fuel pump then operates at normal speed.
This DTC is designed to detect a malfunction in the FUEL PMP relay circuit. When the system is normal, auxiliary battery voltage is applied to the FPR terminal of the ECM while the FUEL PMP relay is off. If auxiliary battery voltage is not applied to the FPR terminal while the FUEL PMP relay is off, the ECM interprets this as a malfunction.

Fig 1: Fuel Pump Primary Circuit

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory
P0230	Fuel Pump Primary Circuit	Open or short in FUEL PMP relay circuit (1 trip detection logic)	Open or short in FUEL PMP relay circuit FUEL PMP relay ECM	Does not come on	DTC stored