Geely JL481Q, Manual

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Fig. 278 fuel pump system circuit diagram
Fig. 279 Measure the voltage between the terminal FC and the ground wire Fig. 280 Examine the open-loop relay
The current that flows through the FC terminal and the open-loop relay coil makes this relay closed, and the fuel pump
begins to work. Due to the NE (engine running) signal, the ECU will keep Tr triggering all the time. If the NE signal disap-
pears, the fuel pump will stop running. The examination steps for fuel pump system circuit is as following:
Fuse
EFI fuse
Lgnition switch
Neutral shift switch
(Automatic shift)
EFI main relay Open-loop relay
Gasoline pump
Starting signal
(Manual shift)
Starting relay
Battery
Starter
Fuse
Ne signal
1. Shut off the ignition and remove the ECU plug.
2. Put on the ignition and use a multimeter to measure the voltage between the
ECU’s FC terminal and the ground wire (See Fig. 279), which should range from 9V
to 14V. If not so, you shall examine the power supply to the ECU.
3. Under normal voltage, if the fuel pump does not work, shut off the ignition switch,
and remove and examine the open-loop relay (See Fig. 280). Between terminals 1
and 2 of the relay there should be connection; between its terminals 3 and 5 there
should be disconnection. When the storage battery’s voltage is imposed between
the terminals 1 and 2, the terminals 3 and 5 will be connected to each other.
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