Page 430 - Foton Workshop Manual - Tunland (AT)

04-284 DIAGNOSTICS - ENGINE CONTROL SYSTEM

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,
04
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 EGR valve faulty circuit?
Is the inspection result normal?

YES>To step 2.
NO>Intermittent trouble exists.

2 . Check EGR valve circuit
(a) Ignition switch: OFF.
(b) Disconnect the battery negative cable.
(c) Disconnect the EGR valve connector E18.
(d) Connect the battery negative cable.
(e) Ignition switch: ON.

(f) Use a multimeter to measure the voltage
between the pin2, 5 of EGR valve connector
E18 and the ground respectively.
Standard voltage

Multimeter connection
Standard value
pin

E18（2）- ground Battery voltage

E18（5）- ground 4.75～5.25 V

Is the inspection result normal?
YES>To step 3.

No > Maintain or replace the harness.

3 . Check EGR valve harness

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