4. Diagnostic Steps:
Note
Before carrying out this diagnosis step, observe the data list on scan tool and analyze the accuracy of the data, as
these will help with quick diagnosis.
Step 1
Use scan tool to carry out idle air control valve action test.
(a)
Connect scan tool to the datalink connector.
(b)
Start engine and turn on the scan tool.
(c)
Select the following: the "Engine"/"Action Test"/"Idle Speed
Control".
(d)
Use scan tool "Function Test" command to enable IAC valve
opening. Increase the speed up to 1,800 rpm and decrease
to 800 rpm, and then increase to 1,800 rpm.
Whether the engine speed follows the instructions rise and fall
steadily?
Yes
No
Step 2
Check the following items.
(a)
Throttle body damage or blockage.
(b)
Is idle air control channel blocked?
(c)
Is there too much residue on the throttle?
(d)
Is there too much residue on the throttle?
(e)
Is there too much residue on the idle air control core shaft?
(f)
Is intake blocked?
Any above mentioned fault?
Yes
Repair the faulty parts. Go to step 10
No
Step 3
Check idle speed control valve.
Idle Control Valve
FE02-5102b
(a)
Turn the ignition switch to "OFF" position.
(b)
Disconnect idle speed control valve wiring harness connector
EN17.
(c)
Measure idle speed control valve resistance.
Tester Connection
Standard Value
AD, BC
40-50 Ω
AC, BD
10 kΩ or higher
(d)
Connect idle speed control valve wiring harness connector
EN17.
Voltage normal?
2-182
Control System JL4G18-D
Engine
EC718/EC718RV EC715/EC715RV 10/2009
Summary of Contents for EC715 2009
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