Page 343 - Foton Workshop Manual - Tunland (AT)

DIAGNOSTICS - ENGINE CONTROL SYSTEM 04-197

DTC inspection
DTC DTC definition Trouble location
conditions
Engine intake mass
• Intake mass flow
flow sensor circuit -
sensor
voltage is above
P356 • Intake mass flow
normal or short circuit 04
to high voltage power • During engine sensor circuit is
supply operation, the open
• The signal circuit in
Engine intake mass diagnosis continues the wire harness or
to run
flow sensor circuit - sensor is short
voltage is higher than circuited to the
P357
normal or short circuit power supply
to high voltage power • ECM
supply

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 fault code related to intake mass flow sensor?

Is the inspection result normal?
YES>To step 2.
NO>Intermittent trouble exists.

2 . Check the intake system
(a) Ignition switch: OFF.
(b) Check whether the intake system is blocked.

Is the inspection result normal?
YES>To step 3.
No >Maintenance related faults.

3 . Check intake mass flow sensor power supply circuit

Page 343