Isuzu 2008MY N Series, Руководство по ремонту

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1A-158 Engine Control System (4HK1)
DTC P0340 (Flash Code 14)
Circuit Description
The camshaft position (CMP) sensor is installed on the
cylinder head at the rear of the camshaft gear. The
CMP sensor detects total of five holes per one engine
cycle (four holes arranged equally every 90
°
and one
reference hole on the camshaft gear surface). The
CMP sensor is a magnetic resistance element (MRE)
type sensor, which generates a square wave signal
pulse. The sensor has the following circuits.
• 5 volts reference circuit
• Low reference circuit
• CMP sensor signal circuit
The ECM monitors both crankshaft position (CKP)
sensor and CMP sensor signal pulses to ensure they
correlate with each other. If the ECM receives a certain
amount of CKP sensor signal pulses without a CMP
sensor signal pulse, this DTC will set.
Condition for Running the DTC
• DTCs P0016, P0335, P0336 and P0341 are not
set.
• The ignition switch is ON.
• The CKP sensor signal pulse is detected.
Condition for Setting the DTC
• The ECM detects that the CMP sensor signal
pulses are not generated during engine rotations.
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.
Condition for Clearing the DTC
• Refer to DTC Type Definitions for Condition for
Clearing the MIL/ DTC - Type A.
Diagnostic Aids
• If an intermittent condition is suspected, refer to
Intermittent Conditions in this section.
• Electromagnetic interference in the CMP sensor
circuits may set this DTC.
• An intermittent CMP sensor signal pulse may set
this DTC.
• Ensure the sensor is tight and the sensor rotor
teeth are not damaged.
Notice: If the CMP sensor signal pulse is lost while
running, the engine will operate normally. If the CMP
sensor signal pulse is not present on start-up, the
engine will not start.
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing DTC P0340
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. If the engine does not start,
crank over the engine for 10 seconds.
4. Monitor the DTC Information with a scan tool.
Does the DTC fail this ignition?
—
Go to Step 3
Go to Diagnostic
Aids
3
Is DTC P0651 also set? —
Go to DTC P0651 Go to Step 4
4
1. Turn OFF the ignition.
2. Disconnect the camshaft position (CMP)
sensor harness connector.
3. Connect a DMM between the 5 volts reference
circuit (pin 3 of E-18) and a known good
ground.
4. Turn ON the ignition, with the engine OFF.
Is the DMM voltage more than the specified
value?
4.5 volts
Go to Step 5 Go to Step 9
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