[GUIDE] How to solve wrong downgrade+fix USB connection to computer (P40Pro+ firmware on P40 Pro / N39 on N29)

[badmania98]

Did you downgrade P40Pro using P40 Pro+ firmware? Maybe this thread can help you.

This is for C432 region only. Do not use this firmware on other region firmware. I can prepare the firmware for other region.


When you downgrade P40Pro firmware using P40Pro+ firmware elements your phone will show like this:

On those phones can use OTG adapter + dload firmware.
The steps:
1. Download the dload firmwares (180 and 202) from this link:

!!!!!!dload N39-N29

Shared file !!!!!!dload N39-N29

s.go.ro

They are not the same firmware as the ones you can find on internet.

2. Unzip 180 firmware and copy dload folder to the memory stick (NM card if OTG is not working)

3. Write 180 firmware using memory-stick + USB-C OTG / NM Card + ProjectMenu\Software Upgrade\1.Memory card Upgrade. To access ProjectMenu, type *#*#2846579#*#* on the original dial app.

At the end will be like this:

4. Use the same procedure with 202 firmware.

At the end will be like this:

5. The USB connection to computer is back now.

6. Use HiSuite proxy to downgrade again using the N29 firmware files (https://www.firmfinder.ml/). After this step you will have N29 back.

At the end will be like this:

7. Now you can install Google, fix the push notifications ( I have the best solution, but is not free) and make update of EMUi to have USB connection to computer and fast charging back.

LE:

a. It is possible to skip to install 180 and write 202 directly, but nobody tried yet. Baby steps.

b. User @bajangg said that ”3. If you choose another Emui 10 version, like Emui 10.0.1.176 and then lost OTA Update, USB Connection, and have no idea what to do, don't afraid. Last time, when i also in the same situation, USB Type C to Type C still working for me and make my device still can connect to HiSuite.” Source: https://forum.xda-developers.com/t/googlefier-install-gms-on-huawei-honor.4180485/post-85627761 I have not tested yet, but if it works you would begin with step 6.
L.E. The transfer files between Computer and phone is available on the downgraded firmware (10.1.x.x) when you use a certain USB-c to USB-c cable. In this case a UGREEN, US355, USB-C To USB-C, 3.1, Gen.2, PD, 5A, 100W, 4K, 10 Gbps cable has been used. In the same time, using the original USB cable or other ordinary USB-c to USB-C cable have not activated the file transfer.

c. You can use a NM card if OTG+Memory card doesn't work. You will download and extract/copy dload firmware on NM card using phone internet connection.




Special thanks to @ciorax who puts in practice and updated my slim idea.

 

[gukitoo]

I had the same problem. When i updated to 11.0.0.202 via OTA the problem was fixed.

 

[starbase64]

someone has an idea for me to downgrade or flash correct region?

My device: P40 Pro C432 (germany)

i have tried this, but flash fail - wrong region
- ELS-LGRP4-OVS 10.1.0.121
- ELS-N29-CUST 10.1.0.8(C432)
- ELS-N29-PRELOAD 10.1.0.2(C432R5)

 

[badmania98]

someone has an idea for me to downgrade or flash correct region?

My device: P40 Pro C432 (germany)

i have tried this, but flash fail - wrong region
- ELS-LGRP4-OVS 10.1.0.121
- ELS-N29-CUST 10.1.0.8(C432)
- ELS-N29-PRELOAD 10.1.0.2(C432R5)

The files are good. Something else is wrong.

 

[starbase64]

what can i do?

 

[badmania98]

what can i do?

As I can see on your images, it doesn't download the files. Server problem or you dont have enough space on the computer partion C:\.

Or your computer partition C:\ is not NTFS formatted (it is FAT 32 only).

 

[starbase64]

all files downloaded

 

[badmania98]

When you get the error? On HiSuite are 2 parts: download part from internet to computer and copy part from computer to phone. Then the phone restarts and writes the firmware.

 

[starbase64]

Error comes after Download. Group Version error is from Hisuite Proxy.

 

[badmania98]

I think that Your HiSuite version is not good.
Use this tutorial, file included in description.

 

[starbase64]

I think that Your HiSuite version is not good.
Use this tutorial, file included in description.

i got always "no internet" error with hisuite 11.0.0.510

 

[badmania98]

Search for HiSuite_11.0.0.550_OVE.exe. Maybe will work. Or the one attached, better.

 

[starbase64]

Search for HiSuite_11.0.0.550_OVE.exe. Maybe will work. Or the one attached, better.

Proxy error with this version

 [08:27:35]: Checking if HISuite is Installed...
 [08:27:36]: HiSuite Exists, Proceeding...
 [08:27:36]: Closing HISuite....
 [08:27:38]: Checking HISuite Version...
 [08:27:39]: HiSuite Version 11 Is Installed, Proceeding....
 [08:27:39]: Patching HISuite Files....
 [08:27:40]: Patch failed, Aborting process....
 [08:27:40]: Please Contact Developer If Error Continues
 [08:27:41]: https://github.com/ProfessorJTJ/HISuite-Proxy/issues

 

[badmania98]

Proxy error with this version

[08:27:35]: Checking if HISuite is Installed...
[08:27:36]: HiSuite Exists, Proceeding...
[08:27:36]: Closing HISuite....
[08:27:38]: Checking HISuite Version...
[08:27:39]: HiSuite Version 11 Is Installed, Proceeding....
[08:27:39]: Patching HISuite Files....
[08:27:40]: Patch failed, Aborting process....
[08:27:40]: Please Contact Developer If Error Continues
[08:27:41]: https://github.com/ProfessorJTJ/HISuite-Proxy/issues

Try the attached one.

 

[starbase64]

10.1.0.550 works ... maybe ... keep your fingers crossed for me

 

[starbase64]

this part is complete and installation process is running

 

[starbase64]

device is still NX9 and USB wont work, but OTA works

 

[badmania98]

That is as it should be at this stage.

 

[starbase64]

USB wont work, now on 11.0.0.151

edit: FW 202 via eRecovery and USB works again

 

[badmania98]

From 193 it will work.