Page 242 - Foton Workshop Manual - Tunland (AT)

04-96 DIAGNOSTICS - ENGINE CONTROL SYSTEM

(c) When terminal contact or mounted parts occur failure, the system might be returned
to its normal state absolutely or temporarily when a questionable part is dismounted
and remounted.
(d) Unless otherwise specified in test process, test ECM and sensors with high-resistance
digital multimeter instead of pointer multimeter.
(e) Do not use a test lamp to test any electric apparatus connected to ECM.
04
(f) The positive and negative poles of battery must not be connected incorrectly, and the
negative pole must be earthed (ground).
(g) ECM and sensors must be protected from moisture. It is not allowed to damage the
sealing gland of ECM or sensors, and it is especially not allowed to rinse ECM and
sensor with water.
(h) Countermeasures against damages to the computer by human-body static electricity:
To test the ECM or replace a chip, the operator must earth his body (earth) by attaching
one end of agrounding ground metal tape to his wrist and the other end to the vehicle
body, so as to prevent the human-body static electricity from damage the computer.
(i) To determine the failure location, it is required to check the condition of the vehicle
when a failure occurs. For example, conduct checks as per the diagnostic trouble code
(DTC) output, and record the conditions before each connector is disconnected or any
part is dismounted and remounted.
(j) Do dismount and remount the ECM, actuators and all independent sensors after the
ignition switch are turned off, unless otherwise specified in the inspection procedures.
(k) If a dismounted and reassembled ECM, actuator or sensor is remounted, the system
shall be checked for normal conditions when assembling is finished. Use special
diagnostic instrument to check DTC
(l) Use a digital multimeter to check the ECM terminals of engine

• Connect a fine probe to the probe of digital multimeter.
• Connect the fine probe to the inside of each terminal (from the inside harness)
of ECM, and measure the magnitude of voltage of the terminals with reference
to the check list.

Page 242