3-94 FUEL SYSTEM (DFI)
Disconnect the fuel pump lead connector and connect
the measuring adapter [A] between these connectors as
Main Harness [B]
Fuel Pump [C]
Special Tool - Measuring Adapter: 57001-1700
Connect a digital meter [D] to the measuring adapter
Fuel Pump Operating Voltage
Connections to Adapter:
Digital Meter (+) → R (pump BK/Y) lead
Digital Meter (–) → BK (pump BK/W) lead
Measure the operating voltage with engine stopped and
with the connector joined.
Turn the engine stop switch run position.
Turn the ignition switch ON.
Standard: Battery Voltage for 3 seconds, and then 0 V
Turn the ignition switch OFF.
If the reading is not the standard, check the fuel pump re-
lay (see Relay Circuit Inspection in the Electrical System
If the fuel pump relay is normal, check the wiring for con-
tinuity (see Fuel Pump Circuit).
Special Tool - Hand Tester: 57001-1394
If the wiring is good, check the ECU for its ground and
power supply (see ECU Power Supply Inspection).
If the ground and power supply are good, replace the ECU
(see ECU Removal/Installation).
If the reading is in the specification, but the pump does
not operate, replace the fuel pump (see Fuel Pump Re-
Pressure Regulator Removal
The pressure regulator [A] is built into the fuel pump and
cannot be removed.