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ZTE Blade Z Max Troubleshooting
The Blade Z Max experiences many of the same faults as other cell phones. The phone is difficult to disassemble and contains many individual parts. Replacement parts for this device are relatively easy to find. Parts such as chargers, screens, speakers, and buttons can be found on popular auction sites.
Device Will Not Charge
When plugged into a wall or car charger, the phone's battery is not replenishing
Check the charger on another phone (be aware that the Blade Z Max uses a USB-C plug). If the charger works on the other phone, skip to the "Check Charging Port" section of this guide. Inspect the charging cord for any tears in the insulation or exposed wire. If any damage is present, replace the cord.
Faulty charging port
Try to charge the phone with a different charger. If this charger also fails to charge the phone, follow the charging port card replacement guide.
Screen is Unresponsive/Picture is Broken
The screen is not responding to touch input, or there are dead/defective pixels
Digitizer (touch screen) is faulty
Hold down the power button on the side of the phone. If the power options menu comes up but the screen is still unresponsive, see the Replace The Screen Digitizer repair guide. If the power menu does not come up, continue to hold the power button until the phone reboots. If the screen works on power up it was simply frozen and your problem is solved. Otherwise, see the screen replacement guide.
LEDs are bad
If the touchscreen works, in the call dialer, dial *983*673636# (*ZTE*OpenEM*), do not press call. This will prompt a pop-up that will inform you that EM (Engineering Mode) is enabled. Dial *983*01#. Select LED Test. This will test all three colors of every pixel. If defective pixels are found, see the screen replacement guide.
Device running slow
Apps load slow, the phone is sluggish at times, or the phone lags behind input
Too many apps running
Go to the device's settings and click on the Memory option. This will list apps/processes that are using the RAM from highest to lowest. Determine if there are any processes that are using an abnormally large amount of memory. If any apps or processes are found that are using an excess of memory, try to force stop them or uninstall them completely if they are not necessary. If this does not solve the problem, it has been reported that expanding the device's internal ROM with an SD card will help the device's speed.
Battery is bad
Plug the device in to supplement the battery power. If this fixes the issue, see the battery replacement guide to remedy the issue.
No/Distorted Sound From Headphones
When trying to play sound through the 3.5mm headphone jack, the sound is either non-existent or distorted
Obstructions in jack
Look inside the jack to check for debris or obstructions. If any debris is present, use a can of compressed air to clear it out. If there appears to not be any obstructions, continue to the Test Speakers section of this guide.
Speakers have failed
In the call dialer, dial *983*673636# (*ZTE*OpenEM*), do not press call. This will prompt a pop-up that will inform you that EM (Engineering Mode) is enabled. Dial *983*01# and select the Speaker Test. This will run a series of test that will check that the speakers are working as well as that the phone is capable of playing sound through the headphone jack. If this test shows that the headphone jack is defective follow the guide to replace the charging port card, which also contains the headphone jack.
Power/Volume Buttons Are Not Responsive
The buttons located on the side of the phone work intermittently or not at all
Debris under buttons
Check that the buttons are depressing when pressed. If they are not, check for any debris that may be obstructing the buttons. If any is found, use compressed air to clear out the obstructions. If the obstructions cannot be reached, follow the Replacing The Power/Volume Buttons repair guide to remove the buttons from the phone for cleaning. If there are no obstructions found, proceed to the Test Buttons section of this guide.
In the call dialer, dial *983*673636# (*ZTE*OpenEM*), do not press call. This will prompt a pop-up that will inform you that EM (Engineering Mode) is enabled. Dial *983*01# and select the Test Buttons option. This will guide you through a test to verify that the buttons are working. If this test finds that the buttons are defective, replace them by following the volume/power button replacement guide.