Isuzu 2008MY N Series, Руководство по ремонту

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1A-170 Engine Control System (4HK1)
DTC P0401 (Flash Code 93)
The ECM controls the EGR valve opening based on the
engine running condition and by controlling the EGR
solenoid. The EGR valve position is detected by the
position sensor, and relayed to the ECM. When the
proper enabling conditions are met, the ECM will open
the EGR valve while monitoring the mass air flow
(MAF) signal. An expected MAF difference should be
detected between the closed and open positions. If the
ECM detects the MAF difference less than expected,
this DTC will set. This DTC will only run once per
ignition cycle within the enabling conditions.
Condition for Running the DTC
• DTCs P0079, P0080, P0102, P0103, P0112,
P0113, P0116, P0117, P0118, P0122, P0123,
P0404, P0409, P0500, P0502, P0503, P0560,
P060B, P0638, P0651, P0697, P1404, P2227,
P2228 and P2229 are not set.
• The battery voltage is between 16 to 32 volts.
• The ignition switch is ON.
Condition for Setting the DTC
• The ECM detects that the MAF amount is not
within the calculated range during the EGR flow
test. This indicates insufficient amount of EGR
flow.
Action Taken When the DTC Sets
• The ECM illuminates the MIL when the diagnostic
runs and fails. Refer to DTC Type Definitions for
Action Taken When the DTC Sets - Type A.
• The ECM limits fuel injection quantity.
Condition for Clearing the DTC
• Refer to DTC Type Definitions for Condition for
Clearing the MIL/ DTC - Type A.
Notice: A history DTC remains 9,600 hours
(accumulated engine runtime) and will not clear with a
scan tool.
Diagnostic Aids
• If an intermittent condition is suspected, refer to
Intermittent Conditions in this section.
• A sticking or intermittently sticking the EGR valve
may set this DTC.
Circuit/ System Testing DTC P0401
Step Action Value(s) Yes No
1
Did you perform the Diagnostic System Check
- Engine Controls?
—
Go to Step 2
Go to Diagnostic
System Check -
Engine Controls
2
1. Install a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine.
4. Monitor the DTC Information with a scan tool.
Is DTC P0101, P0102, P0103 or P0560 also
set?
—
Go to Applicable
DTC Go to Step 3
3
Warm up the engine (allow engine coolant
temperature to reach at least 75
°
C [167
°
F]) and let
idle for at least 3 minutes while observing the DTC
Information with a scan tool.
Does the DTC fail this ignition?
—
Go to Step 4
Go to Diagnostic
Aids
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