GDI ± Troubleshooting
13A-85
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
Damaged rectifier or vortex generation column
Wave pattern characteristics
Unstable wave pattern with non-uniform frequency.
However, when an ignition leak occurs during acceleration,
the wave pattern will be distorted temporarily, even if the
air flow sensor is normal.
CAMSHAFT POSITION SENSOR AND CRANK ANGLE
SENSOR
Measurement Method
1. Disconnect the camshaft position sensor connector and
connect the special tool (test harness: MB991709) in
between. (All terminals should be connected.)
2. Connect the analyzer special patterns pickup to camshaft
position sensor terminal 2.
3. Disconnect the crank angle sensor connector and connect
the special tool (test harness: MB991658) in between.
4. Connect the analyzer special patterns pickup to crank
angle sensor terminal 2.
Alternate Method (Test harness not available)
1. Connect the analyzer special patterns pickup to
engine-ECU terminal 50. (When checking the camshaft
position sensor signal wave pattern.)
2. Connect the analyzer special patterns pickup to
engine-ECU terminal 43. (When checking the crank angle
sensor signal wave pattern.)
Standard Wave Pattern
Observation conditions
Function Special patterns
Pattern height Low
Pattern selector Display
Engine r/min Idle speed
Crank
angle
sensor connector
Camshaft position sensor connector
Analyzer
Special patterns
pick-up