MPI <4G63>
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Troubleshooting
13D-83
Examples of Abnormal Wave Patterns
D
Example 1
Cause of problem
Sensor interface malfunction
Wave pattern characteristics
Rectangular wave pattern is output even when the engine
is not started.
D
Example 2
Cause of problem
Loose timing belt
Abnormality in sensor disk
Wave pattern characteristics
Wave pattern is displaced to the left or right.
INJECTOR
Measurement Method
1.
Disconnect the injector connector, and then connect the
special tool test harness set (MB991348) in between (All
terminals should be connected).
2.
Connect the oscilloscope special patterns pickup to
terminal No. 2 of the injector connector.
Alternate Method (Test harness not available)
1.
Connect the oscilloscope special patterns pickup to
engine-A/T-ECU terminal No. 1 (When checking the No.
1 cylinder).
2.
Connect the oscilloscope special patterns pickup to
engine-A/T-ECU terminal No. 9 (When checking the No.
2 cylinder).
3.
Connect the oscilloscope special patterns pickup to
engine-A/T-ECU terminal No. 24 (When checking the No.
3 cylinder).
4.
Connect the oscilloscope special patterns pickup to
engine-A/T-ECU terminal No. 2 (When checking the No.
4 cylinder).
Special
patterns
pickup
Oscilloscope