Acer AN515-57, Recovering Thunderbolt Controller After Erasing Firmware on UT3 SPI ROM of Intel® JHL8040R Retimer

[Danghaibang]

Hello everyone,

About a year ago, I accidentally erased the firmware on the SPI ROM of a Thunderbolt retimer in my computer, mistaking it for the main BIOS chip. Since then, the Thunderbolt controller no longer appears in Device Manager, and I'm unable to use Thunderbolt functionality.

For context, my system has two retimers: UT5 and UT3. The one I erased is the UT3, which uses a W25Q80DVSSIG chip. In an attempt to fix this, I used a CH341A programmer to copy the ROM data from the UT5 retimer to the UT3, hoping it would restore functionality. Unfortunately, this didn't work, and the Thunderbolt controller still doesn't show up.

I'm wondering if there's any way to reprogram or recover the Thunderbolt functionality at this point. Is there a specific firmware file I need for the UT3 retimer (W25Q80DVSSIG), or perhaps a different approach I should try? Any advice or guidance would be greatly appreciated!

Thanks in advance for your help!

unit: acer nitro 5 AN515-57-727J
model no.: N20C1
S/N: NHQD9SV00513103BD03400
P/N: NH.QD9SV.005
SNID: 13101531234
motherboard number: GH51G LA-L181P Rev:1B 2021-05-24

I attached my current bios file and UT5 bin file below.

Red: UT3 (W25Q80DVSSIG)
Green: main bios chip (XMC 25QH128AHIG), flash using CH341A, neoprogrammer thank to XMC qh128ahig chip - Badcaps #28, choose EON EN25Q128 in neoprogrammer for flashing.

[SMDFlea]

Try post #15 https://www.badcaps.net/forum/troubl...d-a-clean-bios

[Danghaibang]

Try post #15 https://www.badcaps.net/forum/troubl...d-a-clean-bios

Thanks, but the laptop doesn't boot after flash that bin file, the power led only blink a few second and then turn off and the keyboard has no light.

[Danghaibang]

After a few days of diagnosis, I found that the +3VALW is missing, while the +5VALW is okay. I noticed that the 3V_EN_R signal from the EC KB9052QD is also missing, and I don't know why

[mon2]

Test the resistance to ground of +3VALW. Is it low?

No trace break for the enable signal for this rail from the EC?

EC look ok and without visual defect? Being clocked? Power rail to the EC present? The EC is probably dependent on this missing +3VALW rail. Do you have a RTC battery? Voltage?

[Danghaibang]

Test the resistance to ground of +3VALW. Is it low?

No trace break for the enable signal for this rail from the EC?

EC look ok and without visual defect? Being clocked? Power rail to the EC present? The EC is probably dependent on this missing +3VALW rail. Do you have a RTC battery? Voltage?

Thanks for the suggestions. Here's an update based on my measurements:

1. +3VALWP Resistance: I measured the resistance to ground for the +3VALWP rail (at PJ302 / output side of PL301). There doesn't appear to be a short circuit on this rail itself.
2. Enable Signal Trace (3V_EN path): I visually inspected the path for the 3V_EN signal, including the components in its creation circuit (DB1, RB19, RB20 on sheet 84) and the connection towards PU301 (Pin 12). I did not find any obvious trace breaks. The issue seems to be that the enable signal is not being generated correctly upstream.
3. EC Status & Power:
   • The EC (UB1 KB9052QD) appears visually okay, with no obvious damage.
   • Crucially, I re-measured the EC's main standby power: The +3VLP_EC rail (measured directly at EC VCC pins like 9, 22, 33, 96, 111, or at capacitor CB7 after the filter LB1) IS present and stable at 3.3V when the adapter is plugged in. (This corrects my previous finding where I suspected a short after LB1; the EC is receiving its standby power now).
   • I do not have an oscilloscope to verify if the EC is being clocked.
4. EC Dependency & RTC:
   • Regarding EC dependency: Yes, the EC primarily depends on +3VLP_EC (which is now confirmed present). The missing +3VALWP seems to be a result of the EC (or related logic) not providing the necessary enable signal (3V_EN_R -> 3V_EN), rather than the EC depending on +3VALWP.
   • I have an RTC battery, its voltage is ~3.2V. I tested the main issue both with and without the RTC battery installed, and it made no difference. The 0.15V measured at the holder without the battery (and without adapter) seems negligible.

Even with the EC confirmed to have its +3VLP_EC (3.3V) power, the enable signal 3V_EN (which goes to PU301 Pin 12) and RB19 ( pin 1) remains at 0V.

Link to schematic - https://www.badcaps.net/forum/troubl...v-1c-boardview

[Danghaibang]

I think i'll reflash the EC firmware

[mon2]

It will be better to post the schematics inside the dedicated schematic forum so that future readers can find them. Otherwise, SMDFlea will remove you from his Christmas cookies list.

[SMDFlea]

Replaced with a link to the schematics. No cookies from me, not even a crumb :-(