Modifying EM7455 so my HP Laptop accepts it
Posted: Fri Apr 16, 2021 10:20 am
<r>I have a relatively recent HP Elitebook with a WWAN slot. I understand it has a whitelist of accepted LTE cards. A while ago, I bought an HP branded EM7355 (HP lt4211). This is not one of the approved cards, so every time I boot the laptop with it inserted, it'll throw an error saying the card isn't approved. But I hit enter to continue booting and the card works.<br/>
<br/>
I just bought an EM7455 because I want more bands, cat 6, and to give it an identity crisis to use it with an AT&T phone line. HP does not have a branded version of the EM7455 so I bought the Dell one. When I put it in the HP, it doesn't give me that error screen but it doesn't allow the OS to see it at all.<br/>
<br/>
I have an older Dell with no whitelist, and when I put the 7455 in it, it works perfectly. So I know the card works.<br/>
<br/>
I've tried changing the VID, PID, USBPRODUCT...nothing works. I've tried changing those values to match the HP branded 7355. I'd expect the error screen to come up, but nothing happens. I tried making it look like an HP lt4120 or lt4132 (the only cards that actually shipped with the laptop) no dice.<br/>
<br/>
I wonder if it could be AT!USBMANUFACTURER that gets filtered by the bios. On the HP branded one, it's set to HP. On the 7455 it's set to "Sierra Wireless, Inc." AT!USBMANUFACTURER doesn't work:<br/>
<CODE><s></e></CODE>
even after OPENLOCK, OPENMEP and OPENCND.<br/>
<br/>
The bios seems to check whether the card is approved every 30 sec or so. I can boot with the 7355 and hot swap to the 7455, and it'll work for a few seconds before the laptop goes uhh nope and cuts power to the m.2 slot. It won't power the slot again until a reboot.<br/>
<br/>
I've spent like 6 hours on this and I'm stumped. Any ideas?</r>
<br/>
I just bought an EM7455 because I want more bands, cat 6, and to give it an identity crisis to use it with an AT&T phone line. HP does not have a branded version of the EM7455 so I bought the Dell one. When I put it in the HP, it doesn't give me that error screen but it doesn't allow the OS to see it at all.<br/>
<br/>
I have an older Dell with no whitelist, and when I put the 7455 in it, it works perfectly. So I know the card works.<br/>
<br/>
I've tried changing the VID, PID, USBPRODUCT...nothing works. I've tried changing those values to match the HP branded 7355. I'd expect the error screen to come up, but nothing happens. I tried making it look like an HP lt4120 or lt4132 (the only cards that actually shipped with the laptop) no dice.<br/>
<br/>
I wonder if it could be AT!USBMANUFACTURER that gets filtered by the bios. On the HP branded one, it's set to HP. On the 7455 it's set to "Sierra Wireless, Inc." AT!USBMANUFACTURER doesn't work:<br/>
<CODE><s>
Code: Select all
</s><i>
</i>AT!USBMANUFACTURER?
Sierra Wireless, Inc
AT!USBMANUFACTURER="HP"
OK
AT!USBMANUFACTURER?
Sierra Wireless, Inc
<e>even after OPENLOCK, OPENMEP and OPENCND.<br/>
<br/>
The bios seems to check whether the card is approved every 30 sec or so. I can boot with the 7355 and hot swap to the 7455, and it'll work for a few seconds before the laptop goes uhh nope and cuts power to the m.2 slot. It won't power the slot again until a reboot.<br/>
<br/>
I've spent like 6 hours on this and I'm stumped. Any ideas?</r>