Make sure you’re pressing and holding RST. While holding RST, press and hold UDL. Let go of RST and continue to hold UDL until STAT LED displays Z-modem blink. If it doesn’t go into Z-modem may be bad CPUA board. Is WD LED lit? Do you have 1.5, 3.3 & 5VDC? Is the 3V coin cell battery good? It’s possible the board may be completely unprogrammed with no software whatsoever. Also the software files you’re trying to install need to be in a folder labeled update inside a folder labeled tke - all lower case.
