Wondered if anyone may have an idea, incase this is a simple, easily sorted issue.
Unboxed & tested a new Zero today, & all I’m getting is this.
Power on, & the display turns an orange/red hue, & nothing else happens. Doesn’t boot, no logo displayed etc.
I’ve contacted the seller to let them know it’s faulty, but if it’s something easily remedied, I’d rather just sort it than go through a return & replace scenario.
Hi @Lion
Are you aware of this issue?
Check the screen cable…pull if off & insert it again…other than that, you’ll have to deal with the seller.
Already tried that. Also tried it with a display from one of the other Zero’s. No change.
You could try attaching a HDMI display and see if Linux is booting.
Another thought, Plug in wired ethernet, look at your router client list. If the Zero gets an IP assigned then SSH in.
Instructions to reload the software/firmware at Image File - Google Drive
Requires a EMMC dongle
It’d never crossed my mind to try a hdmi display. I’ll give that a whirl, & see if it supplies any useful info. Cheers. 
Have you tried to reflash the firmware?
Not as yet. I have dug out a spare EMMC card/module & writer I had knocking about though, so hopefully I’ll get chance to try that tomorrow. Downloading the image from Drive as we speak.
Let us know how it goes once you’ve reinstalled the firmware
Will do. Fingers crossed that’s all it is, causing the issue.
From your error it would appear your HOST software is intact. Rewriting it may not help. More likely you need to flash one/both MCU(s).
I’d go into fluidd or mainsail and look for serial and CAN devices.
Thicko question coming up. 
MCU’s; Printhead pcb & screen unit pcb?
The screen is probably okay, it is connected TO the main MCU. Without instructions from the MCU nothing gets displayed. The MCU does nothing without instructions from klipper. The HDMI connects to Linux at boot as a system device. KlipperScreen launches after boot runs in parallel with klippy.
Your error message calls out [mcu] not [extra_mcu] in the toolhead. NOTE: Your HOST (H616) and the main MCU are both on the same circuit board but Klipper handles them as separate devices.
Most likely the mainboard didn’t enjoy the container ship ride and a so-so solder joint (or similar) broke in transit. BUT if you can find a valid CAN address it is possible that re-flashing the MCU could revive it.
Thanks cardoc. I’ve finally had chance to have another look at this. I flashed another emmc card & fitted it, just to completely rule that aspect out, but as you advised, it’s made no difference. Same error message appearing.
How would I go about trying to find a valid CAN address?
Looked at the Mainsail interface, & that devices option wasn’t there. With it erroring, it appears to be only loading part of that.
Hopefully, I may have a replacement motherboard due to be sent. The seller has suggested they’ll send a replacement motherboard & EMMC module. So, fingers crossed.
The seller is sending a replacement motherboard.
In the meantime, I may try & follow that guide on finding a CAN address, if time allows, & see if it is possible to work round a situation like this.
I replaced my motherboard in the Zero. It was easy, nothing to do but swap out the wires.
The replacement board arrived earlier this week. Should hopefully have chance to fit it this weekend.
