There could be a few reasons why your digital multimeter (DMM) is not giving accurate results when measuring the output of your laptop charger.
One reason could be that the charger is not providing a stable voltage output. Many laptop chargers have a switching power supply, which can cause voltage fluctuations that a basic DMM may not be able to accurately measure.
Another reason could be that the DMM is not properly calibrated or has malfunctioned. It is possible that the DMM’s internal components have been damaged or that the device needs to be calibrated. It’s always recommended to check the manual or the manufacturer’s website for calibration instructions or troubleshooting steps.
Additionally, the DMM’s measurement leads may not be properly connected to the charger. It’s important to ensure that the leads are securely connected to the charger’s output terminals and that they are not touching any other metal parts, as this can cause measurement errors.
It’s also possible that the charger is not working properly and is not providing the correct voltage output. In this case, the DMM would be measuring the faulty output and providing inaccurate results.
In any case, it’s always a good idea to compare the measurement results of your DMM with those of another multimeter or a reference measurement device to confirm the accuracy of your readings. If you still have doubts, you can contact the manufacturer for further support or take your device to a professional for a proper diagnosis.