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Polar M400 Troubleshooting
The Polar M400 Watch monitors the user’s training data, including heart rate, speed, distance and route.
- Device Won't Power On
- Wrist Strap is Loose
- Screen Does Not Respond
- Polar H7 Bluetooth Heart Rate Sensor Malfunctions
- Speed and Distance Not Reporting
Device Won't Power On ¶
You hold down the power button on the right side of the watch and it will not turn on, no matter the length or duration of the hold.
Lack of charge in battery ¶
Symptom typically caused by lack of charge in the battery. For this, a power cord is provided. Can be plugged into USB ports. Make sure the charging area is dry and clean. Ensure the charging cable and USB ports both work. If all of those are applicable, it is likely an issue with the battery itself and not the charging components.
Damaged or wet battery ¶
Symptom could be caused by a damaged or wet battery. For this, try drying the charging area and cable. Make sure when not charging, the seal over the charging port is closed to avoid water or other general damage. Make sure the charging cable does not get wet as well. If it gets wet, attempt to dry or submerge in rice and attempt to plug in charger to see if it turns back on and maintains a charge.
Wrist Strap is Loose ¶
The wrist strap does not connect/stay on wrist.
Excessive wear and tear ¶
Symptom typically caused by excessive wear and tear during workouts. For this, it is recommended to keep the strap maintained. There is an alternate wrist band provided by Amazon that can be purchased to replace the original one if damaged. There is a video on the support forum on the Polar website that provides detailed feedback on how to change the wristband.
Wearing in wet conditions ¶
Another possible symptom can be caused by wearing the Polar M400 in wet conditions (e.g., rain and shower). To minimize this, attempt to keep the wristband dry most of the time. The watch is water resistant for up to 30-meters; however, it is not recommended to press any buttons under any level of water because they will not register with the device, and it will not track your heart rate under any level of water.
Screen Does Not Respond ¶
The screen is exhibiting odd colors, a black screen, or has multiple cracks, inhibiting your ability to use the watch.
Heavy impact with watch (e.g., dropping it) ¶
Symptom typically caused by dropping watch on a hard surface or if a heavy object falls on the watch. To avoid dropping it, ensure the watch is secured on wrist. It is also best to avoid high intensity interval training (HIIT). When not in use, keep the M400 Watch in a safe place out of reach of children and animals. Place in secure location when not in use such as the original packaging. In addition, there are cases available on Amazon for purchase to keep the watch safe and avoid breaking.
Submerged in water 30+ meters ¶
An additional symptom of this could be caused by submerging the watch in more than 30-meters of water. To avoid this, do not wear watch in large bodies of water, as it says on the Polar support forum that it is not intended for scuba diving purposes. Also avoid leaving the device in the sun, as it may not work to its full potential if the screen gets too hot.
Polar H7 Bluetooth Heart Rate Sensor Malfunctions ¶
Common concerns with the H7 Heart Rate Sensor is that it is no longer paired with either the user or devise, or is not displaying a reading.
Heart Rate Sensor is missing beats over time ¶
This issue occurs frequently upon changing batteries, especially with active athletes. It is recommended that the user "re-pair" First, ensure that you are far (roughly 33 ft) from any other Bluetooth Smart heart rate sensor users, and make sure that you have the correct device that your H7 is paired with. If the H7 Sensor is already paired, then delete the sensor. To re-pair, wear H7 as you would normally, making sure it is flat against the skin with the Polar logo in the upright position, and moisten the Heart Rate Sensor's electrodes . On your mobile device, access the Polar Beat Application. Select "settings," then select "general," and then "HR Sensor." From the HR Sensor screen, there should be a red "Pair" button in the top-right corner of the screen, across from the ID number. Press button and your H7 should re-pair.
Heart Rate Symbol is not flashing at all ¶
If the H7 is providing no reading, common issues is the heart rate sensor battery may be empty or the H& is not being maintained. Make sure to keep the transmitter clean by using water and mild soap, such as Dove Cream Beauty Bathing Bar or Jergens Mild Soap, then dry with a soft cloth. Make sure to avoid moisturizing soaps, and do not soak, iron, dry clean or bleach the strap. The electrodes on the strap for the H7 will not work without moisture, so put water on them and ensure the strap is tight. Also, make sure there is no electromagnetic interference in the immediate area, such as cell phones, high power lines, or televisions. Finally, be mindful of ways to avoid problems with your Polar heart rate monitor. The transmitter for the H7 should never be bent, so make sure it is worn correctly, to prevent stretching the strap or bending the electrode areas, and stored the H7 in a secured location that is preferably cool and dry. Furthermore, to prevent snap oxidation, clean and dry, as suggested above, after every use to keep from staying wet from sweat or water after a workout.
Speed and Distance Not Reporting ¶
The Polar M400 watch has uses GPS technology to report speed and distance. At times, the GPS will not work and your progress will not be logged.
Data File Has Expired ¶
The most common cause of the GPS not working is that the data file, housing the information for the GPS to work, has expired. This is fairly normal. You can see if the GPS file has expired by navigating the following path on the M400: Settings> General settings > About your product> A-GPS exp. If your GPS file has expired, you will need to update the software. Connect your device to your computer and launch the FlowSync software or the Flow app to update the A-GPS data.
Accessing Satellites ¶
If your GPS file has not expired, there is probably a problem with your watch accessing the satellites. This would most likely happen when you are using the watch in proximity to tall buildings and trees. Additionally, using the watch while its face is facing down could interfere with the GPS function. You can go to an open outdoor space with the watch facing up in order to catch the GPS satellite signals.