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Fuel Injector Valves




Check electrical function:
[D] 300 - In this case, the fuel Injector valves are driven with a frequency of 10 Hz. The pulse period is 1 ms in order to avoid fuel being injected. Activation can be felt with the hand.

Check pulse duration:
The pulses can be tested with the multimeter [M] 15 at the injector valve connector. Note that only parallel injection is possible during diagnostic mode. Therefore, when the pulse duration is measured with the multimeter (not in diagnostic mode), the pulse duration is doubled for semisequential injection.

Test with oscilloscope [M] 22 and universal adapter:
Connect terminal frequency OFF (+) to terminal 1 (black) and apply frequency 70 Hz, connect terminal D+ (blue) to Pin 16 or 17. The injection signal should be displayed on the oscilloscope. In contrast to pulse duration measurement, the injection fade-out when coasting is also displayed.

Resistance test:
The resistance of an injector valve can be measured directly at the component. Only the entire injector valve group (-3 valves) can be measured at the universal adapter. For technical data, see Appendix.