Page 334 - Foton Workshop Manual - Tunland (AT)

04-188 DIAGNOSTICS - ENGINE CONTROL SYSTEM

DTC inspection
DTC DTC definition Trouble location
conditions
Engine fuel pump
booster assembly 1
circuit - voltage is
P271
04 below normal or
shorted to low voltage • When the key
switch is in ON • Fuel pump actuator
power supply
position, the • The fuel pump
Engine fuel pump diagnosis continues actuator connector
booster assembly 1 to run. is in poor contact
circuit - voltage is and the wiring
P272
above normal or harness is broken
shorted to high or shorted
voltage power supply • ECM

• During engine
Electronic fuel
operation, the
P2311 injection control valve diagnosis continues
circuit - fault exists
to run

Diagnosis Procedure

NOTICE

• To implement the following steps, ensure that ECM is grounded properly.
• Before conducting electric diagnosis, do refer to the reference circuit diagram
and the element information.
• Before conducting measurement, check the pins of connectors for rupture,
looseness and rust, and ensure that the pins are contacted properly.
• If the connection is good, check the sensor signal voltage when moving the
connector and harness. If a fault occurs, the voltage display on the diagnostic
instrument will change.

1 . DTC inspection
(a) Ignition switch: OFF.
(b) Connect the diagnostic apparatus.
(c) Use the diagnostic apparatus, read the fault code.
(d) Confirm whether there is a fault code related to engine fuel pump booster assembly?

Is the inspection result normal?
YES>To step 2.

NO>Intermittent trouble exists.

2 . Check engine fuel pump booster assembly wire harness
(a) Ignition switch: OFF.
(b) Disconnect the battery negative cable.
(c) Disconnect the engine fuel pump booster assembly connector E11.
(d) Disconnect connector E01 of ECM.

Page 334