Nano fails to verify

I have a Nano which fails to verify though others do verify correctly.
I attempted to program 'blink' and the LED doesn't respond correctly.
Attached is a copy of the programming messages.

Do I need a new Nano or should I attempt to reprogram the bootloader?

nano error.txt (17.8 KB)

Do I need a new Nano or should I attempt to reprogram the bootloader?

Try burning the bootloader if you have an Arduino or another programmer like a USBasp or USBtinyISP.

I have another nano and a uno - I guess I could use either?
The board doesn't have ICSP pins soldered and if I fitted them I would have to remove them again or it won't fit on the application board.
So must I use the ICSP pins or can I connect to the equivalent pins - D11, D12, D13, RST, +5V, GND?

So must I use the ICSP pins or can I connect to the equivalent pins - D11, D12, D13, RST, +5V, GND?

You can use the equivalent pins. Use the Arduino that would be easiest to hookup.

https://www.arduino.cc/en/Tutorial/ArduinoISP

It doesn't want to play. I get invalid device signature 0xFFFFFF.

Using the same board as programmer and the same connections I could program the bootloader in a Uno so I think it's time for a new Nano :frowning:

I agree.

Device sig 0xFFFFFF can mean that MISO is shorted to Vcc (or you wired it wrong) - Doublecheck connections with your DVM before you trash the nano. Also check that all the applicable pins are connected (for example, if Gnd wasn't connected, but Vcc was, I think you'd get this result too). I recommend always doing this when there are inexplicable problems bootloading - particularly when using Arduino as ISP, since there are twice as many connection points to screw up.

(also, a trick relating to ICSP headers - if you have a cable with 2x3 connector on it, you can plug a 2x3 piece of pin header into it, put it into the holes, and hold it in place, with a gentle sideways pressure to make sure the pins make contact - that's how I bootload the boards I sell)

I measured resistances from the bare Nano pins to both supplies:

+5V 0V
D10 11M inf
D11 230 560
D12 57 345
D13 11M inf

It certainly looks like D11 and D12 are borked.