Crankshaft Position Sensor: Testing and Inspection
CAMSHAFT POSITION SENSOR AND CRANKSHAFT POSITION SENSORRequired Special Tools:
- MB991709: Test Harness
- MB991658: Test Harness
Measurement Method
1. Disconnect the camshaft position sensor connector and connect the test harness special tool (MB991709) between the separated connector. (All terminals should be connected.)
2. Connect the oscilloscope probe to camshaft position sensor connector terminal No.2.
3. Disconnect the crankshaft position sensor intermediate connector and connect the test harness special tool (MB991658) between the separated connector.
4. Connect the oscilloscope probe to crankshaft position sensor connector terminal No.2 (black clip of special tool).
Alternate method (Test harness not available)
1. Connect the oscilloscope probe to ECM
2. Connect the oscilloscope probe to ECM
Standard Wave Pattern
Wave Pattern Observation Points
Check that cycle time T becomes shorter when the engine speed increased.
Examples of Abnormal Wave Patterns
Example 1
- Cause of problem
Sensor interface malfunction.
- Wave pattern characteristics
Rectangular wave pattern is output even when the engine is not started.
Example 2
- Cause of problem
Loose timing belt. Abnormality in sensor disc.
- Wave pattern characteristics
Wave pattern is displaced to the left or right.