Vain pump type fuel pump which is driven by electric motor is applied to this vehicle. Fuel pump which is installed inside of fuel tank supplies fuel to high pressure pump. ECM controls Fuel pump relay to supply power to low pressure fuel pump. The relay operates for 1.5 sec. for the diagnosis fuel pump relay at IG KEY ON, then if engine speed above 45rpm is detected by CKPS, relay turns ON and fuel is supplied to high pressure pump.
P0231 is set when no current or excessively low current is detected in fuel pump relay control circuit for more than 1 sec. at Fuel pump relay ON condition. This code is due to open or short to ground in glow relay control circuit or internal open in Fuel pump relay component.
Item | Detecting Condition | Possible Cause | ||
DTC Strategy | ● Voltage monitoring | ● Fuel pump relay control circuit ● Fuel pump relay component | ||
Enable Conditions | ● IG KEY "ON" (monitoring only performed within relay operating condition) | |||
Threshold Value | ● Short to GND ● Wiring open | |||
Diagnostic Time | ● 1.0 sec. | |||
Fail Safe | Fuel Cut | NO | ||
EGR Off | NO | |||
Fuel Limit | NO | |||
Check Lamp | OFF |
Relay Coil Resistance | Motor Type | Pumping Pressure |
75±10Ω(20℃) | Electric motor type vein pump | 4 - 5 bar |