Camshaft Position Sensor: Testing and Inspection
SETTING UP TO MEASURE WAVE PATTERNSMeasurement Method Using Special Tool Harness
1. Disconnect the distributor connector and connect the special tool (test harness: MB991348) in between. (All terminals should be connected).
2. Connect the analyzer special patterns pickup to terminal (1) of the distributor connector. (When inspecting the camshaft position sensor signal wave pattern.)
3. Connect the analyzer special patterns pickup to terminal (2) of the distributor connector. (When inspecting the crankshaft position sensor signal wave pattern.)
Alternative method (when test harness is not available)
1. Connect the analyzer special patterns pickup to ECM terminal (68) for the camshaft position sensor.
2. Connect the analyzer special patterns pickup to ECM terminal (69) for the crankshaft position sensor.
STANDARD WAVE PATTERN
Observation conditions set to the following:
Function: Special patterns
Pattern height: Low
Pattern selector: Display
Engine rpm: Idling (700 rpm)
Wave pattern observation points
Check that cycle time "T" becomes shorter and the frequency increases when the engine speed is increased.
EXAMPLES OF ABNORMAL WAVE PATTERNS
Cause of problem: Malfunction of sensor interface
Wave pattern characteristics: Short wave pattern is output even when the engine is not started.
Cause of problem: Loose timing belt/Abnormality in sensor disk
Wave pattern characteristics: Wave pattern is displaced to the left or right.