Page 243 - Foton Workshop Manual - Tunland (AT)

DIAGNOSTICS - ENGINE CONTROL SYSTEM 04-97

WARNING

• When the ignition switch is set to ON and the connectors are disconnected
during diagnosis, other system may store the DTC. When the job is finished,
verify the failure codes of all systems. Delete any DTC if available.To connect
or disconnect the connector, set the ignition switch to its “LOCK” (OFF)
position. 04
• Do not insert the testing probe into the harness for testing, so as not to
deteriorate the water-repellent property and lead to corrosion. Use special tools
such as testing harness, harness connector or inspection connectors.
• To check ordinary (non waterproof) connectors when the harness connectors
are connected, insert the probe from the harness; if the connector is too small
for insertion of the testing probe (for example the ECM connector), do not conduct
insertion barely.
• To conduct checks when the connector is not connected (check male terminals):
• Caution: The used testing probe must not lead to short circuit of connector
terminals so as not to damage the interior circuits of ECM.
• When the connector is disconnected, the system to be checked or other systems
may store the trouble code.

• To conduct checks when the harness connector is not connected (check female
terminals):
• Use special tools designed for harness checks. Forced probe insertion may
lead to poor contact.
• When the connector is disconnected, relevant system to be checked or other
systems may store the trouble code.

• Short-circuit caused by incorrect terminal insertion may damage the harness,
sensor ECM or other elements. Be careful!
• It is unnecessary to conduct checks as per the sequence listed in the check list.

• If the results of voltage are different from the standard value, check relevant
sensors, actuators and harness, and repair or replace them when necessary.
• When repair or replacement is finished, use a voltmeter to check the values
over again, and verify whether or not the failure is eliminated.

(m) Use a multimeter to check the resistance and conduction between the ECM terminals
• Ignition Switch: OFF.
• Remove the connectors of ECM harness.
• As per the check list, measure and check the resistance and conduction between
the terminals of harness-side connectors of ECM.

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