INFOR Huawei (HarmonyOS) testpoint cable (Huawei USB COM 1.0)

[vadino3767]

Due to some changes done by Huawei, phones that are updated to HarmonyOS, would not present the Huawei USB COM 1.0 serial port after test pointing. Without the Huawei USB COM 1.0 serial port UnlockTool cannot communicate to these devices in factory/bootrom mode.
You need to use a modified USB cable, we call it the "Harmony TP Cable". If this cable is used, Huawei USB COM 1.0 serial port is available and all Chimera factory/bootrom mode service functions will work on HarmonyOS models.
Harmony TP Cable, How-to
What you need:

• 1 pc. 150 Ohm (150 Ω) resistor
• 1 pc. 270 Ohm (270 Ω) resistor
• 1 pc. 1.5 kiloohm (1.5 kΩ) resistor
• and 1 pc. standard USB cable

Here is how-to make the cable:

and its simplified modification:

Important Notes

• You still have to test point (this cable only works if the test pointing is done)
• Make sure that you always connect the cable to the phone first
• Make sure, when asked to disconnect you always disconnect the cable from the computer first
• You have to see the Huawei USB COM 1.0 serial port in Windows Device Manager. If you cannot see it, most probably the modified cable is wrong.

 

[vadino3767]

the test of two variants of the cable scheme for the test point was successful)))