Isuzu 4HL1, Workshop Manual

Page: 207 / 267

Engine Control System 1A-205
7
Check the idle position switch circuit (switch to
switch connector) for open wiring.
1. Disconnect the idle position switch
connector.
2. Measure the resistance between the idle
position switch connector pins while
operating the switch with a finger.
Was the resistance within range?
Switch-on
(switch is
released):
50
Ω
, max.
Switch-off
(switch is
pressed):
∞ Ω
Go to Step 8 Go to Step 10
8
Check the idle position switch circuit (ground
circuit) for open wiring.
1. Measure the resistance between idle
position switch connector (ECM side) pin
2 and ground (e.g., frame or body).
Was the resistance within range?
0
Ω
Go to Step 9 Go to Step 10
9
Check the idle position switch circuit (ECM to
switch connector) for open wiring.
1. Disconnect the ECM.
2. Jumper the idle position switch connector
pin and measure the resistance at the
ECM connector.
Was the resistance within range?
Pins 110-87:
0
Ω
Go to Step 11 Go to Step 10
10
Repair or replace the faulty harness.
Is the action complete?
—
Go to Step 13 —
11
Review the DTC.
1. Certainly connect the idle position switch
and ECM connectors.
2. Using Tech 2, clear the DTC.
3. Perform test run and review the DTC.
Is DTC241 detected?
—
Go to Step 12
Refer to
Diagnostic Aids
12
1. Replace the ECM.
IMPORTANT:
If necessary (for the vehicle equipped with
idle stop function), input the number of
startups to the replacing ECM.
Is the action complete?
—
Verify repair and
go to Step 13 —
13
Check DTC241 will not be set again.
1. Using Tech 2, clear the DTC.
2. Perform test run and review the DTC.
Is DTC241 detected?
—
Refer to
Diagnostic Aids
and go to Step 2
Repair is
complete
Step Action Value(s) Yes No