The two signal waveforms of the intake camshaft are merged, resulting in malfunction of the sensor function. The reasons for signal merging are: MB SD C4 Diagnostic tool sensor hardware failure, sensor installation location failure, signal generator failure. Because the sensor has been replaced before, you can exclude the sensor MB SD C4 hardware failure; because the sensor mounting position is fixed, so they measured the camshaft 4 signal leaves to the fixed sensor position, the results show that there is a signal leaf and the other three signal leaves The distance is less than 0.9mm.

Link of MB SD Connect Compact 4:

    It is this 0.9mm distance leading to the MB SD C4 sensor signal acquisition is not normal. Use the tool to correct the deformation of the signal leaves, measurement meet the requirements, install the sensor, remove the fault code, start the engine again, the engine on the instrument failure alarm light is no longer lit. Go out to test, everything back to normal. At this point, the car's fault was really completely removed by hand.


    Maintenance Summary: This car Opel Opcom v1.95 in the replacement of the camshaft after the failure, over-reliance on the computer given the diagnostic results, while ignoring Opcom V1.95 the meaning of the first fault code, that is, the sensor function failure, and no analysis of the system control logic, Which led to miscarriage of justice, and missed itself without failure of the intake camshaft adjustment sprocket and Opel Opcom control valve. It can be seen, to become a good car diagnostic division, it should be like the detection of suspense case, can not let go of any clues, so accurate analysis, lean evidence, in order to better and more accurately find the real source of failure.


    Expert Comments: After reading this article, I was very dissatisfied with the heart. As a front-line technical staff, but also high-end brand vehicle maintenance of Launch X431 V 8 inch technical personnel, in the troubleshooting, is this to carry out troubleshooting repair it?

As a modern vehicle maintenance, the use of professional equipment has long been commonplace, after reading the fault code, in addition to follow the Launch X431 v instructions in the maintenance manual to check, the use of oscilloscopes to verify the fault waveform is also necessary to do the work, so that more Accurately find the cause of the X431 malfunction, unfortunately, the author did not do so, which also laid the foreshadowing for the subsequent failure.