Isuzu 2008MY N Series Workshop Manual page 271

1A-268 Engine Control System (4HK1)
Step
1. Turn OFF the ignition.
2. Disconnect the accelerator pedal position
(APP) sensor harness connector.
3. Inspect
connections and corrosion at the harness
connector of the APP sensor (pins 1, 2, 3, 4,
5, and 6 of B-5).
4. Disconnect the ECM harness connector.
4
5. Inspect
connections and corrosion at the harness
connector of the ECM (pins 41, 42, 60, 61, 63
and 64 of J-14).
6. Test for high resistance on each sensor circuit.
7. Repair the connection(s) or circuit(s) as
necessary.
Did you find and correct the condition?
1. Test the signal circuits between the ECM (pins
63 and 64 of J-14) and the APP sensor (pins 2
and 5 of B-5) for a short circuit each other.
5
2. Repair the circuit(s) as necessary.
Did you find and correct the condition?
Replace the APP sensor. Refer to Accelerator
Pedal Sensor in Section 1I Engine Speed Control
6
System.
Did you complete the replacement?
1. Reconnect
harness connector(s).
2. Clear the DTCs with a scan tool.
3. Turn OFF the ignition for 30 seconds.
4. Start the engine.
7
5. Fully depress and release the accelerator
pedal while observing the DTC Information
with a scan tool.
Does the DTC fail this ignition?
Important:
programmed and learned.
8
Replace the ECM. Refer to ECM Replacement.
Did you complete the replacement?
1. Reconnect
harness connector(s).
2. Clear the DTCs with a scan tool.
3. Turn OFF the ignition for 30 seconds.
4. Start the engine.
9
5. Fully depress and release the accelerator
pedal while observing the DTC Information
with a scan tool.
Did the DTC fail this ignition?
Observe the DTC Information with a scan tool.
10
Are there any DTCs that you have not
diagnosed?
Action
for an intermittent,
for an intermittent,
all previously disconnected
Replacement ECM
all previously disconnected
Value(s)
for poor
—
for poor
—
—
—
must be
—
—
—
Yes
Go to Step 9 Go to Step 5
Go to Step 9 Go to Step 6
Go to Step 7
Go to Step 8 Go to Step 10
Go to Step 9
Go to Step 2 Go to Step 10
Go to DTC List
No
—
—
System OK