A pulse-width-modulated signal conveys information through switching behaviour. A meter’s average voltage can therefore miss details that matter to interpreting the signal. The correct expected waveform and method depend on the device.
Ask what the test measured
Keep frequency, duty-cycle information and the operating condition when the technician records them. An average reading is not a universal pass or fail criterion. Some sensors use entirely different interfaces, so identification comes first.
Do not inject a guessed signal into the controller to see whether a warning clears. A specialist should compare the supported measurement with the system information. The report should explain how the observed signal relates to the physical condition being measured and the customer’s complaint.
Need help with this fault?
- Sensor Signal Stays Fixed While the Physical Condition Changes
- Replacement Sensor Has the Same Plug but a Different Range
Browse this collection or prepare a vehicle and module enquiry. Tell us about the vehicle, the fault and any tests already done. Contact our Didcot workshop before travelling or posting a module. Visits are by appointment.